Tag Archives: Develop

Verifying your Google Assistant media action integrations on Android

Posted by Nevin Mital, Partner Developer Relations

The Media Controller Test (MCT) app is a powerful tool that allows you to test the intricacies of media playback on Android, and it's just gotten even more useful. Media experiences including voice interactions via the Google Assistant on Android phones, cars, TVs, and headphones, are powered by Android MediaSession APIs. This tool will help you verify your integrations. We've now added a new verification testing framework that can be used to help automate your QA testing.

The MCT is meant to be used in conjunction with an app that implements media APIs, such as the Universal Android Music Player. The MCT surfaces information about the media app's MediaController, such as the PlaybackState and Metadata, and can be used to test inter-app media controls.

The Media Action Lifecycle can be complex to follow; even in a simple Play From Search request, there are many intermediate steps (simplified timeline depicted below) where something could go wrong. The MCT can be used to help highlight any inconsistencies in how your music app handles MediaController TransportControl requests.

Timeline of the interaction between the User, the Google Assistant, and the third party Android App for a Play From Search request.

Previously, using the MCT required a lot of manual interaction and monitoring. The new verification testing framework offers one-click tests that you can run to ensure that your media app responds correctly to a playback request.

Running a verification test

To access the new verification tests in the MCT, click the Test button next to your desired media app.

MCT Screenshot of launch screen; contains a list of installed media apps, with an option to go to either the Control or Test view for each.

The next screen shows you detailed information about the MediaController, for example the PlaybackState, Metadata, and Queue. There are two buttons on the toolbar in the top right: the button on the left toggles between parsable and formatted logs, and the button on the right refreshes this view to display the most current information.

MCT Screenshot of the left screen in the Testing view for UAMP; contains information about the Media Controller's Playback State, Metadata, Repeat Mode, Shuffle Mode, and Queue.

By swiping to the left, you arrive at the verification tests view, where you can see a scrollable list of defined tests, a text field to enter a query for tests that require one, and a section to display the results of the test.

MCT Screenshot of the right screen in the Testing view for UAMP; contains a list of tests, a query text field, and a results display section.

As an example, to run the Play From Search Test, you can enter a search query into the text field then hit the Run Test button. Looks like the test succeeded!

MCT Screenshot of the right screen in the Testing view for UAMP; the Play From Search test was run with the query 'Memories' and ended successfully.

Below are examples of the Pause Test (left) and Seek To test (right).

MCT Screenshot of the right screen in the Testing view for UAMP; a Pause test was run successfully. MCT Screenshot of the right screen in the Testing view for UAMP; a Seek To test was run successfully.

Android TV

The MCT now also works on Android TV! For your media app to work with the Android TV version of the MCT, your media app must have a MediaBrowserService implementation. Please see here for more details on how to do this.

On launching the MCT on Android TV, you will see a list of installed media apps. Note that an app will only appear in this list if it implements the MediaBrowserService.

Android TV MCT Screenshot of the launch screen; contains a list of installed media apps that implement the MediaBrowserService.

Selecting an app will take you to the testing screen, which will display a list of verification tests on the right.

Android TV MCT Screenshot of the testing screen; contains a list of tests on the right side.

Running a test will populate the left side of the screen with selected MediaController information. For more details, please check the MCT logs in Logcat.

Android TV MCT Screenshot of the testing screen; the Pause test was run successfully and the left side of the screen now displays selected MediaController information.

Tests that require a query are marked with a keyboard icon. Clicking on one of these tests will open an input field for the query. Upon hitting Enter, the test will run.

Android TV MCT Screenshot of the testing screen; clicking on the Seek To test opened an input field for the query.

To make text input easier, you can also use the ADB command:

adb shell input text [query]

Note that '%s' will add a space between words. For example, the command adb shell input text hello%sworld will add the text "hello world" to the input field.

What's next

The MCT currently includes simple single-media-action tests for the following requests:

  • Play
  • Play From Search
  • Play From Media ID
  • Play From URI
  • Pause
  • Stop
  • Skip To Next
  • Skip To Previous
  • Skip To Queue Item
  • Seek To

For a technical deep dive on how the tests are structured and how to add more tests, visit the MCT GitHub Wiki. We'd love for you to submit pull requests with more tests that you think are useful to have and for any bug fixes. Please make sure to review the contributions process for more information.

Check out the latest updates on GitHub!

Introducing Android 9 Pie

Posted by Dave Burke, VP of Engineering

After more than a year of development and months of testing by early adopters, we're ready to launch Android 9 Pie, the latest release of Android, to the world.

Android 9 harnesses the power of machine learning to make your phone smarter, simpler, and tailored to you. Read all about the new consumer features here. For developers, Android 9 includes many new ways to enhance your apps and build new experiences to drive engagement.

You've given us tons of feedback along the way--over a thousand bugs and feature requests--thank you! More than 140,000 of you tried our preview builds through the Android Beta program, and seven of our device maker partners also brought our Beta to their flagship devices, enabling users around the world to give their feedback too.

Today we're pushing the source code to Android Open Source Project (AOSP), and starting the Android 9 rollout to all Pixel users worldwide, with Android 9 coming to many more devices in the coming months.

We continue to move Android forward as the premier open platform for developers worldwide to build their businesses. With Android 9 -- together with the powerful new capabilities in Google Play for apps and games -- we're committed to helping you build great experiences, as well as reach and engage the right users safely and cost-effectively around the world.

What's in Android 9?

A smarter smartphone, with machine learning at the core

Android 9 helps your phone learn as you use it, by picking up on your preferences and adjusting automatically. Everything from helping users get the most out of their battery life to surfacing the best parts of the apps they use all the time, right when they need it most, Android 9 keeps things running smoother, longer.

Adaptive Battery

We partnered with DeepMind on a feature called Adaptive Battery that uses machine learning to prioritize system resources for the apps the user cares about most. If your app is optimized for Doze, App Standby, and Background Limits, Adaptive Battery should work well for you right out of the box. If you haven't yet taken optimized your app, make sure to check out the details in the power documentation to see how it works.

Slices

Slices can help users perform tasks faster by enabling engagement outside of the fullscreen app experience. It does this by using UI templates that can display rich, dynamic, and interactive content from your app from within the Google Search app and later in other places like the Google Assistant. You can learn more about building Slices to enhance your app here.

App Actions

App Actions is a new way to raise the visibility of your app and drive engagement. Actions take advantage of machine learning to surface your app to the user at just the right time, based on your app's semantic intents and the user's context.

We'll be sharing more details in the coming weeks on registering your app to handle one or more user intents, so your apps can be enabled for App Actions and surfaced across multiple Google and Android surfaces in response to user queries.

Text Classifier and Smart Linkify

We've extended the ML models that identify entities in content or text input to support more types like Dates and Flight Numbers through the TextClassifier API. Smart Linkify lets you take advantage of the TextClassifier models through the Linkify API, including enriched options for quick follow-on user actions. Smart Linkify also delivers significant improvements in accuracy of detection as well as performance.

Neural Networks API 1.1

Android 9 adds an updated version of the Neural networks API, to extend Android's support for accelerated on-device machine learning. Neural Networks 1.1 adds support for nine new ops -- Pad, BatchToSpaceND, SpaceToBatchND, Transpose, Strided Slice, Mean, Div, Sub, and Squeeze. A typical way to take advantage of the APIs is through TensorFlow Lite.

Getting the most from your phone -- more easily

We're excited about making your smartphone more intelligent. But it's also important that the technology fades to the back for users. In Android 9, we've evolved Android's UI to be simpler and more approachable -- for developers, these changes help improve the way users find, use, and manage your apps.

New system navigation

Android 9 introduces a new system navigation that we've been working on for more than a year. The new design helps make Android's multitasking more approachable and makes discovering apps much easier. You can swipe up from anywhere to see full-screen previews of recently used apps and simply tap to jump back into one of them.

Display cutout

Now your app can take full advantage of the latest edge-to-edge screens through display cutout support in Android 9. For most apps, supporting display cutout is seamless, with the system managing status bar height to separate your content from the cutout. If you have immersive content, you can use the display cutout APIs to check the position and shape of the cutout and request full-screen layout around it. To help with development and testing, we've added a Developer Option that simulates several cutout shapes on any device.

Apps with immersive content can display content fullscreen on devices with a display cutout.

Notifications and smart reply

Android 9 makes notifications even more useful and more actionable. Messaging apps can take advantage of the new MessagingStyle APIs to show conversations, attach photos and stickers, and even suggest smart replies. You'll soon be able to use ML Kit to generate smart reply suggestions for your app.

MessagingStyle notifications with conversations and smart replies [left], images and stickers [right].

Text Magnifier

In Android 9 we've added a Magnifier widget to improve the user experience of selecting text. The Magnifier widget lets users precisely position the cursor or the text selection handles by viewing zoomed text through a draggable pane. You can attach it to any view that is attached to a window, so you can use it in custom widgets or during custom text-rendering. The Magnifier widget can also provide a zoomed-in version of any view or surface, not just text.

Check out our recent blog post for more about this and other Text features, such as PrecomputedText and line height and baseline text alignment.

Security and privacy for users

Biometric prompt

With a range of biometric sensors in use for authentication, we've made the experience more consistent across sensor types and apps. Android 9 introduces a system-managed dialog to prompt the user for any supported type of biometric authentication. Apps no longer need to build their own dialog--instead they use the BiometricPrompt API to show the standard system dialog. In addition to Fingerprint (including in-display sensors), the API supports Face and Iris authentication.

If your app is drawing its own fingerprint auth dialogs, you should switch to using the BiometricPrompt API as soon as possible. See this post for more information.

Protected Confirmation

Android 9 introduces Android Protected Confirmation, which uses the Trusted Execution Environment (TEE) to guarantee that a given prompt string is shown and confirmed by the user. Only after successful user confirmation will the TEE then sign the prompt string, which the app can verify.

Stronger protection for private keys

We've added StrongBox as a new KeyStore type, providing API support for devices that provide key storage in tamper-resistant hardware with isolated CPU, RAM, and secure flash. You can set whether your keys should be protected by a StrongBox security chip in your KeyGenParameterSpec.

DNS over TLS

Android 9 adds built-in support for DNS over TLS, automatically upgrading DNS queries to TLS if a network's DNS server supports it. Users can manage DNS over TLS behavior in a new Private DNS Mode in Network & internet settings. Apps that perform their own DNS queries can use a new API, LinkProperties.isPrivateDnsActive(), to check the DNS mode. More in this post.

HTTPS by default

As part of a larger effort to move all network traffic away from cleartext (unencrypted HTTP) to websites secured with TLS (HTTPS), we're changing the defaults for Network Security Configuration to block all cleartext traffic. You'll now need to make connections over TLS, unless you explicitly opt-in to cleartext for specific domains. See the details here.

Compiler-based security mitigations

In Android 9 we've expanded our use of compiler-level mitigations to harden the platform through run-time detection of dangerous behavior. Control Flow Integrity (CFI) techniques help to prevent code-reuse attacks and arbitrary code execution. In Android 9 we've greatly expanded CFI usage within the media framework and other security-critical components, such as NFC and Bluetooth. We've also introduced CFI kernel support into the Android common kernel when building with LLVM.

We've also expanded our use of Integer overflow sanitizers to mitigate memory-corruption and information-disclosure vulnerabilities. We've prioritized sanitizers in libraries with past vulnerabilities or where complex untrusted input is processed, such as libui, libnl, libmediaplayerservice and others. See this post for details.

Privacy for users

Android 9 safeguards privacy in a number of new ways. The system now restricts access to mic, camera, and all SensorManager sensors from apps that are idle. While your app's UID is idle, the mic reports empty audio and sensors stop reporting events. Cameras used by your app are disconnected and will generate an error if the app tries to use them. In most cases, these restrictions should not introduce new issues for existing apps, but we recommend removing these requests from your apps.

Android 9 also gives the user control over access to the platform's build.serial identifier by putting it behind the READ_PHONE_STATE permission. To access the build.serial identifier, you should use the Build.getSerial() method.

Read more about all of the privacy changes here.

New experiences in camera, audio, and graphics

Multi-camera API and other camera updates

With Android 9 you can now open streams from two or more physical cameras simultaneously on devices that support the multi-camera API. On devices with either dual-front or dual-back cameras, you can create innovative features not possible with just a single camera, such as seamless zoom, bokeh, and stereo vision. The API also lets you call a logical or fused camera stream that automatically switches between two or more cameras.

Other improvements in camera include new Session parameters that help to reduce delays during initial capture, and Surface sharing that lets camera clients handle various use-cases without the need to stop and start camera streaming. We've also added APIs for display-based flash support and access to OIS timestamps for app-level image stabilization and special effects.

HDR VP9 Video and HEIF image compression

Android 9 adds built-in support for HDR VP9 Profile 2, so you can now deliver HDR-enabled movies to your users on HDR-capable devices.

We're excited to add HEIF (heic) image encoding to the platform. HEIF is a popular format for photos that improves compression to save on storage and network data. With platform support on Android 9 devices, it's easy to send and utilize HEIF images from your backend server. Once you've made sure that your app is compatible with this data format for sharing and display, give HEIF a try as an image storage format in your app. You can do a jpeg-to-heic conversion using ImageDecoder or BitmapFactory to obtain a bitmap from jpeg, and you can use HeifWriter in the AndroidX library to write HEIF still images from YUV byte buffer, Surface, or Bitmap.

Enhanced audio with Dynamics Processing

The Dynamics Processing API lets you use a new audio effect to isolate specific frequencies and lower loud or increase soft sounds to enhance the acoustic quality of your app. For example, you can improve the sound of someone who speaks quietly in a loud, distant or otherwise acoustically challenging environment. The API gives you access to a multi-stage, multi-band dynamics processing effect that includes a pre-equalizer, a multi-band compressor, a post-equalizer and a linked limiter.

ImageDecoder for bitmaps and drawables

An ImageDecoder API gives you an easier way to decode images to bitmaps or drawables. You can create a bitmap or drawable from a byte buffer, file, or URI. The API offers several advantages over BitmapFactory, including support for exact scaling, single-step decoding to hardware memory, support for post-processing in decode, and decoding of animated images. You can read more here.

Connectivity and location

Wi-Fi RTT for indoor positioning

Android 9 lets you build indoor positioning features into your apps through platform support for the IEEE 802.11mc Wi-Fi protocol -- also known as Wi-Fi Round-Trip-Time (RTT). On Android 9 devices with hardware support, location permission, and location enabled, your apps can use RTT APIs to measure the distance to nearby Wi-Fi Access Points (APs). The device doesn't need to connect to the APs to use RTT, and to maintain privacy, only the phone is able to determine the distance, not the APs.

Knowing the distance to 3 or more APs, you can calculate the device position with an accuracy of 1 to 2 meters. With this accuracy you can support use-cases like in-building navigation; fine-grained location-based services such as disambiguated voice control (e.g. 'Turn on this light'); and location-based information (e.g. 'Are there special offers for this product?').

Data cost sensitivity in JobScheduler

JobScheduler is Android's central service to help you manage scheduled tasks or work across Doze, App Standby, and Background Limits. In Android 9, JobScheduler handles network-related jobs better for the user, coordinating with network status signals provided separately by carriers. Jobs can now declare their estimated data size, signal prefetching, and specify detailed network requirements—carriers can report networks as being congested or unmetered. JobScheduler then manages work according to the network status. For example, when a network is congested, JobScheduler might defer large network requests. When unmetered, it can run prefetch jobs to improve the user experience, such as prefetching headlines.

Open Mobile API for NFC payments and secure transactions

Android 9 adds an implementation of the GlobalPlatform Open Mobile API to Android. On supported devices, apps can use the OMAPI API to access secure elements (SE) to enable smart-card payments and other secure services. A hardware abstraction layer (HAL) provides the underlying API for enumerating the variety of Secure Elements (eSE, UICC, and others) available.

Performance for apps

ART performance

Android 9 brings performance and efficiency improvements to all apps through the ART runtime. We've expanded ART's use of execution profiles to optimize apps and reduce the in-memory footprint of compiled app code. ART now uses profile information for on-device rewriting of DEX files, with reductions up to 11% across a range of popular apps. We expect these to correlate closely with reductions in system DEX memory usage and faster startup times for your apps.

Optimized for Kotlin

Kotlin is a first-class language on Android, and if you haven't tried it yet, you should! We've made an enduring commitment to Kotlin in Android and continue to expand support including optimizing the performance of Kotlin code. In Android 9, you'll see the first results of this work--we've improved several compiler optimizations, especially those that target loops, to extract better performance. We're also continuing to work in partnership with JetBrains to optimize Kotlin's generated code. You can get all of the latest Kotlin performance improvements just by keeping Android Studio's Kotlin plugin up-to-date.

Today, we are also releasing an update to the Android 9 - API 28 SDK (rev. 6), which contains nullability annotations in some of the most frequently used APIs. We'll provide more details about this in an upcoming post.

Modern Android

As part of Android 9 we are modernizing the foundations of Android and the apps that run on it, as part of our deep, sustained investments in security, performance, and stability.

As we announced last year, Google Play will require all app updates to target Android Oreo (targetSdkVersion 26 or higher) by November 2018. In line with that, if your app targets a platform earlier than Android 4.2 (API level 17), users installing it will see a warning dialog after that day. Here's a checklist of resources for help and support as you migrate -- we're looking forward to seeing your apps getting the most from modern Android.

Get your apps ready for Android 9!

With Android 9 coming to Pixel users starting today, and to other devices in the months ahead, it's important to test your app for compatibility as soon as possible. Just install your current app from Google Play on a device or or emulator running Android 9. As you work through the flows, make sure your app runs and looks great, and that it handles the Android 9 behavior changes properly.

Also watch for uses of non-SDK interfaces in your app. Android 9 restricts access to selected non-SDK interfaces, so you should reduce your reliance on them. See our recent post for details.

After you've made any necessary updates, we recommend publishing to Google Play right away. without changing the app's platform targeting. This lets you ensure a great experience for Android 9 users while you work on enhancing your app with Android 9 APIs and targeting.

Enhance your app with Android 9 features and APIs

When you're ready, dive into Android 9 and build with the new features and APIs in Android 9.

To get started, just download the official API 28 SDK and the latest tools and emulator images into Android Studio 3.1, or use the latest version of Android Studio 3.2. Then update your project's compileSdkVersion and targetSdkVersion to API 28. When you change your targeting, make sure your app supports all of the applicable behavior changes.

As soon as you're ready, publish your APK updates to Google Play. A common strategy is to use Google Play's beta testing feature to get early feedback from a small group of users and then do a staged rollout to production.

Visit the Android 9 site for details and developer documentation. Also check out this video and the Google I/O Android Playlist for more on what's new in Android 9 for developers.

Coming to a device near you

Starting today, an over-the-air update to Android 9 will begin rolling out to Pixel phones. And devices that participated in the Beta program from Sony Mobile, Xiaomi, HMD Global, Oppo, Vivo, OnePlus, and Essential, as well as all qualifying Android One devices, will receive this update by the end of this fall! We are also working with a number of other partners to launch or upgrade devices to Android 9 this year.

As always, the system images for Pixel devices are available here for manual flash and download. If you're looking for the Android 9 source, you'll find it here in the Android Open Source Project repository under the Android 9 branches.

What's next?

Now that we've reached the official release, we're bringing the Developer Preview to a close. We'll soon be closing the Developer Preview issue tracker to new issues, so if you have feedback, feel free to file a new issue against Android 9 in the AOSP issue tracker.

Thanks again to the many developers and early adopters who participated in the Android 9 Developer Preview and public beta. Your contributions have been critical to making the Android 9 platform a great one for developers and consumers.

Supporting display cutouts on edge-to-edge screens

Posted By Megan Potoski, Product Manager, Android System UI

Smartphones are quickly moving towards smaller bezels and larger aspect ratios. On these devices, display cutouts are a popular way to achieve an edge-to-edge experience while providing space for important sensors on the front of the device. There are currently 16 cutout devices from 11 OEMs already released, including several Android P beta devices, with more on the way.

These striking displays present a great opportunity for you to showcase your app. They also mean it's more important than ever to make sure your app provides a consistently great experience across devices with one or two display cutouts, as well as devices with 18:9 and larger aspect ratios.

Examples of cutout devices: Essential PH-1 (left) and Huawei P20 (right).

Make your app compatible with display cutouts

With many popular and upcoming devices featuring display cutouts, what can you do to make sure your app is cutout-ready?

The good news is, for the most part your app should work as intended even on a cutout device. By default, in portrait mode with no special flags set, the status bar will be resized to be at least as tall as the cutout and your content will display in the window below. In landscape or fullscreen mode, your app window will be letterboxed so that none of your content is displayed in the cutout area.

However, there are a few areas where your app could have issues on cutout devices.

  • Watch out for any sort of hard-coding of status bar height -- this will likely cause problems. If possible, use WindowInsetsCompat to get status bar height.
  • In fullscreen, be careful to consider when to use window vs. screen coordinates, as your app will not take up the whole screen when letterboxed. For example, if you use MotionEvent.getRawX/Y() to get screen coordinates for touch events, make sure to transform them to the view's coordinates using getLocationOnScreen().
  • Pay special attention to transitions in and out of fullscreen mode.

Here are a few guidelines describing what issues to look out for and how to fix them.

Take advantage of the cutout area

Rendering your app content in the cutout area can be a great way to provide a more immersive, edge-to-edge experience for users, especially for content like videos, photos, maps, and games.

An example of an app that has requested layout in the display cutout.

In Android P we added APIs to let you manage how your app uses the display cutout area, as well as to check for the presence of cutouts and get their positions.

You can use layoutInDisplayCutoutMode, a new window layout mode, to control how your content is displayed relative to the cutout. By default, the app's window is allowed to extend into the cutout area if the cutout is fully contained within a system bar. Otherwise, the window is laid out such that it does not overlap with the cutout. You can also set layoutInDisplayCutoutMode to always or never render into the cutout. Using SHORT_EDGES mode to always render into the cutout is a great option if you want to take advantage of the full display and don't mind if a bit of content gets obscured by the cutout.

If you are rendering into the cutout, you can use getDisplayCutout() to retrieve a DisplayCutout that has the cutout's safe insets and bounding box(es). These let you check whether your content overlaps the cutout and reposition things if needed.

<style name="ActivityTheme">
  <item name="android:windowLayoutInDisplayCutoutMode">
    default/shortEdges/never
  </item>
</style>

Attribute for setting layoutInDisplayCutoutMode from the Activity's theme.

For devices running Android 8.1 (API 27), we've also back-ported the layoutInDisplayCutoutMode activity theme attribute so you can control the display of your content in the cutout area. Note that support on devices running Android 8.1 or lower is up to the device manufacturer, however.

To make it easier to manage your cutout implementation across API levels, we've also added DisplayCutoutCompat in the AndroidX library, which is now available through the SDK manager.

For more about the display cutout APIs, take a look at the documentation.

Test your app with cutout

We strongly recommend testing all screens and experiences of your app to make sure that they work well on cutout devices. We recommend using one of the Android P Beta Devices that features a cutout, such as the Essential PH-1.

If you don't have a device, you can also test using a simulated cutout on any device running Android P or in the Android Emulator. This should help you uncover any issues that your app may run into on devices with cutouts, whether they are running Android 8.1 or Android P.

What to expect on devices with display cutouts

Android P introduces official platform support for display cutouts, with APIs that you can use to show your content inside or outside of the cutout. To ensure consistency and app compatibility, we're working with our device manufacturer partners to mandate a few requirements.

First, devices must ensure that their cutouts do not negatively affect apps. There are two key requirements:

  • In portrait orientation, with no special flags set, the status bar must extend to at least the height of the cutout.
  • In fullscreen or landscape orientation, the entire cutout area must be letterboxed.

Second, devices may only have up to one cutout on each short edge of the device. This means that:

  • You won't see multiple cutouts on a single edge, or more than two cutouts on a device.
  • You won't see a cutout on the left or right long edge of the device.

Within these constraints, devices can place cutouts wherever they want.

Special mode

Some devices running Android 8.1 (API level 27) or earlier may optionally support a "special mode" that lets users extend a letterboxed fullscreen or landscape app into the cutout area. Devices would typically offer this mode through a toggle in the navigation bar, which would then bring up a confirmation dialog before extending the screen.

Devices that offer "special mode" allow users to optionally extend apps into the cutout area if supported by the app.

If your app's targetSdkVersion is 27 or higher, you can set the layoutInDisplayCutoutMode activity theme attribute to opt-out of special mode if needed.

Don't forget: larger aspect ratios too!

While you are working on cutout support, it's also a great time to make sure your app works well on devices with 18:9 or larger aspect ratios, especially since these devices are becoming increasingly common and can feature display cutouts.

We highly encourage you to support flexible aspect ratios so that your app can leverage the full display area, no matter what device it's on. You should test your app on different display ratios to make sure it functions properly and looks good.

Here are some guidelines on screens support to keep in mind as you are developing, also refer to our earlier post on larger aspect ratios for tips on optimizing. If your app can't adapt to the aspect ratios on long screens, you can choose to declare a max aspect ratio to request letterboxing on those screens.

Thanks for reading, and we hope this helps you deliver a delightful experience to all your users, whatever display they may have!

Final preview update, official Android P coming soon!

Posted By Dave Burke, VP of Engineering

Android P is almost here! As we put the finishing touches on the new platform, today we're bringing you Android P Beta 4.

Beta 4 is the last preview milestone before we launch the official Android P platform later this summer. Take this opportunity to test your apps and publish updates, to make sure you offer a great experience for users transitioning to Android P!

What's in this update?

Today's Beta 4 update includes a release candidate build with final system behaviors and the official Android P APIs (API level 28), available since Beta 2. It includes everything you need to wrap up your testing in time for the upcoming official Android P release.

Get your apps ready for Android P

With the consumer launch coming soon, it's important to test your app for compatibility with Android P. Just install your current app from Google Play on an Android P Beta device or emulator. As you work through the flows, make sure your app runs and looks great, and that it handles the Android P behavior changes properly.

Also watch for uses of non-SDK interfaces in your app. Android P restricts access to selected non-SDK interfaces, so you should reduce your reliance on them. See our recent post for details..

After you've made any necessary updates, we recommend publishing to Google Play right away without changing the app's platform targeting. This lets you ensure a great experience for Android P users while you work on enhancing your app with Android P APIs and targeting.

Enhance your app with Android P features and APIs

When you're ready, dive into Android P and learn about the new features and APIs that you can use in your apps, like multi-camera support, display cutout, enhanced notifications, ImageDecoder, TextClassifier, and others.

To build with the new APIs, just download the official API 28 SDK and tools into Android Studio 3.1, or use the latest version of Android Studio 3.2. Then update your project's compileSdkVersion and targetSdkVersion to API 28. When you change your targeting, make sure your app supports all of the applicable behavior changes.

As soon as you're ready, publish your APK updates that are compiled against, or optionally targeting, API 28. A common strategy is to use Google Play's beta testing feature to get early feedback from a small group of users and then do a staged rollout to production.

Visit the Developer Preview site for details and documentation. Also check out this video and the Google I/O Android playlist for more on what's new in Android P for developers.

How do I get Beta 4?

It's easy - you can get Android P Beta 4 on Pixel devices by enrolling here. If you're already enrolled in our Android Beta program, you'll automatically get the Beta 4 update soon. As always, downloadable system images for Pixel devices are also available. Partners who are participating in the Android P Beta program will also be updating their devices to Beta 4 over the coming weeks.

What's next?

Stay tuned for the official Android P launch coming soon! You can continue to share your feedback or requests in the meantime, and feel free to use our hotlists for platform issues, app compatibility issues, and third-party SDK issues.

Thanks for your feedback so far, and thank you to everyone who participated in our recent Reddit AMA on r/androiddev!

Congrats to the new Android Excellence apps and games on Google Play

Posted by Kacey Fahey, Developer Marketing, Google Play

Join us in congratulating the latest apps and games entering the Android Excellence program on Google Play. This diverse group of apps and games is recognized for their high quality, great user experience, and strong technical performance. Whether you're interested in learning meditation or a new language, or are looking for a game about butterflies or warships, we're excited to dive in to these new collections.

Winning apps image

Check out a few of our highlighted apps.

  • Beelinguapp: Learn a new language with this unique app. Read and listen to stories with side by side text of the language you're learning, while following along with your language as a reference.
  • Fortune City: If you're looking for a fun app to help manage your personal finances, learn how Fortune City teaches good budgeting habits as you build a prospering metropolis.
  • ShareTheMeal: Feed a child in need with one tap on your phone, or create a team to fight hunger together with your friends, using this app by the World Food Programme.

Test your skills with these highlighted games.

  • Animal Crossing™: Pocket Camp: Take on the role of campsite manager as you collect items to decorate and build your ultimate dream campsite. Meet animals, build friendships and invite your favorite animals over for a fun time.
  • Cash, Inc.: Be the big boss of your business empire in this fun game. Work your way up to join a community of business elites and become the most famous money tycoon.
  • Shadowgun Legends: Save humanity from an alien invader in an epic Story Campaign spanning over 200+ mission on 4 diverse planets. Along the way, customize your character, team up with friends, and become a celebrity of the Shadowgun Universe.

See the full list of Android Excellence apps and games.

New Android Excellence apps New Android Excellence games
Beelinguapp
BTFIT
Fortune City
Letras.mus.br
LingoDeer
Memrise
PicsArt
Pocket Casts
ShareTheMeal
The Mindfulness App
Tokopedia
Trello
VivaReal
Wynk Music
Animal Crossing™: Pocket Camp
Cash, Inc.
Flutter: Starlight
Shadow Fight 3
Shadowgun Legends
War Heroes
World of Warships Blitz

Explore other great apps and games in the Editors' Choice section on Google Play and discover best practices to help you build quality apps and games.

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Android P Beta 3 is now available

Posted by Dave Burke, VP of Engineering

Android P logo

Today we're rolling out Beta 3 of Android P, our next milestone in this year's Android P developer preview. With the developer APIs already finalized in the previous update, Beta 3 now takes us very close to what you'll see in the final version of Android P, due later this summer.

Android P Beta 3 includes the latest bug fixes and optimizations for stability and polish, together with the July 2018 security updates. It's a great way to test your apps now to make sure they are ready before the final release. Give Beta 3 a try and let us know what you think!

You can get Android P Beta 3 on Pixel devices by enrolling here. If you're already enrolled and received the Android P Beta 2 on your Pixel device, you'll automatically get the update to Beta 3. Partners who are participating in the Android P Beta program will also be updating their devices to Beta 3 over the coming weeks.

What's in this update?

Today's preview update includes the Beta 3 system images for Pixel devices and the Android Emulator, as well as an update to the Android Studio build tools to include D8 as independent tool. Beta 3 is an early release candidate build of Android with near-final system behaviors and the official Android P APIs (API level 28).

With the Beta 3 system images and updated build tools, you've got everything you need to test your apps or extend them with Android P features like multi-camera support, display cutout, enhanced notifications, ImageDecoder, TextClassifier, and many others. In your testing, make sure to account for App standby buckets, privacy restrictions, and restrictions on non-SDK interfaces.

Get started in a few simple steps

Android P preview

First, make your app compatible and give your users a seamless transition to Android P. Just install your current app from Google Play on an Android P Beta device or emulator and test -- the app should run and look great, and handle the Android P behavior changes properly. After you've made any necessary updates, we recommend publishing to Google Play right away without changing the app's platform targeting.

If you don't have a supported device, remember that you can instead set up an Android Virtual Device on the Android Emulator for your test environment. If you haven't tried the emulator recently, you'll find that it's incredibly fast, boots in under 6 seconds, and even lets you model next-gen screens -- such as long screens and screens with a display cutout.

Next, update your app's targetSdkVersion to 28 as soon as possible, so Android P users of your app can benefit from the platform's latest security, performance, and stability features. If your app is already targeting API 26+ in line with Google Play's upcoming policies, then changing to target API 28 should be a small jump. When you change your targeting, make sure your app supports all of the applicable behavior changes.

It's also important to test your apps for uses of non-SDK interfaces and reduce your reliance on them. As noted recently, Android P restricts access to selected non-SDK interfaces. Watch for logcat warnings that highlight direct uses of restricted non-SDK interfaces and try the new StrictMode method detectNonSdkApiUsage() to catch accesses programmatically. Where possible, you should move to using public equivalents from the Android SDK or NDK. If there's no public API that meets your use-case, please let us know.

When you're ready, dive into Android P and learn about the new features and APIs that you can use in your apps. To build with the new APIs, just download the official API 28 SDK and tools into Android Studio 3.1, or use the latest version of Android Studio 3.2. Then update your project's compileSdkVersion and targetSdkVersion to API 28.

Visit the Developer Preview site for details and documentation. Also check out this video and the Google I/O Android playlist for more on what's new in Android P for developers.

Publish to Google Play alpha, beta, or production channels

As soon as you're ready, publish your APK updates that are compiled against, or optionally targeting, API 28. Publishing an update to Google Play during the preview lets you push updates to existing users to test compatibility on their devices.

To make sure that your updated app runs well on Android P as well as older versions, a common strategy is to use Google Play's beta testing feature. With beta testing you can get early feedback from a small group of users -- including Beta 3 users — and then do a staged rollout to production.

What's next?

Thanks for all of your feedback so far. Please continue to share feedback or requests as we work towards the consumer release later this summer. Feel free to use our hotlists for platform issues, app compatibility issues, and third-party SDK issues.

Also, the Android engineering team will host a Reddit AMA on r/androiddev to answer your technical questions about Android P on July 19 from 11:30-1 PM (Pacific Time). Look out for an announcement on r/androiddev in the coming weeks. We look forward to addressing your questions!

Android P Beta 2 and final APIs!

Posted By Dave Burke, VP of Engineering

Android P Logo

Four weeks ago at Google I/O we released the first beta version of Android P, putting AI at the core of the operating system and focusing on intelligent and simple experiences.

We talked about some of Android's newest features in the keynotes and went deep on the developer APIs during the breakouts. If you missed the livestream, make sure to check out the full playlist of Android talks.

Today we're releasing Android P Beta 2, an update that includes the final Android P APIs, the latest system images, and updated developer tools to help you get ready for the consumer release coming later in the summer.

You can get Android P Beta 2 on Pixel devices by enrolling here. If you're already enrolled and received the Android P Beta 1 on your Pixel device, you'll automatically get the update to Beta 2. Partners that are participating in the Android P Beta program will be updating their devices over the coming weeks.

Enhance your app with Android P features and APIs

Android P Beta 2 is the latest update of our upcoming Android P platform and includes the final APIs (API level 28) as well as the official SDK. You can get started building with the Android P features and APIs today. Here are a few we want you to try -- head over to the features overview for more.

Machine learning at the core

Adaptive battery image

We partnered with DeepMind on a feature we call Adaptive Battery that uses machine learning to prioritize system resources for the apps the user cares about most. If your app is optimized for Doze, App Standby, and Background Limits, Adaptive Battery should work well for you right out of the box. Make sure to check out the details in the power documentation to see how it works and where the impacts could be, and test your apps to make sure they are ready.

App Actions is a new way to help you raise the visibility of your app and help drive engagement. Actions take advantage of machine learning on Android to surface your app to the user at just the right time, based on your app's semantic intents and the user's context. Actions work on Android P and earlier versions of the platform and they'll be available soon for you to start using. Sign up here to be notified when Actions are available.

Slices are a new way to surface rich, templated content in places like Google Search and Assistant. They're interactive, and through Android Jetpack they're compatible all the way back to KitKat. Check out the Getting Started guide to learn how to build with Slices -- you can use the SliceViewer tool to see how your Slices look. Over time we plan to expand the number of places that your Slices can appear, including remote display in other apps.

Simplicity, polish

Android P adds platform support for screens with display cutouts, and we've added new APIs to let you deliver a rich, edge-to-edge experience on the latest screens. Cutout support works seamlessly for apps, with the system managing status bar height to separate your content from the cutout. If you have immersive content, you can use the display cutout APIs to check the position and shape of the cutout and request full-screen layout around it.

All developers should check out the docs to learn how to manage the cutout area and avoid common compatibility issues that can affect apps. Make sure to test your app on a device that has a display cutout, such as one of the Android P Beta devices.

Immersive content display.

Apps with immersive content can display content fullscreen on devices with a display cutout.

If your app uses messaging notifications, take advantage of the changes in MessagingStyle that make notifications even more useful and actionable. You can now show conversations, attach photos and stickers, and even suggest smart replies. You'll soon be able to use ML Kit to generate smart reply suggestions your app.

MessagingStyle notifications MessagingStyle notifications

MessagingStyle notifications with conversations and smart replies [left], images and stickers [right].

Security

Verify purchase icon

With a range of biometric sensors in use for authentication, we've made the experience more consistent across sensor types and apps. Android P introduces a system-managed dialog to prompt the user for any supported type of biometric authentication. Apps no longer need to build their own dialog -- instead they use the BiometricPrompt API to show the standard system dialog. In addition to Fingerprint (including in-display sensors), the API supports Face and Iris authentication.

If your app is drawing its own fingerprint auth dialogs, you should switch to using the BiometricPrompt API as soon as possible.

More

If your app uses the device camera, try the new multi-camera APIs that let you access streams simultaneously from two or more physical cameras. On devices with dual cameras, you can create innovative features not possible with a single camera -- such as seamless zoom, bokeh, and stereo vision. You can get started today using any of the Android P Beta devices that offers a dual camera.

Audio apps can use the Dynamics Processing API for access to a multi-stage, multi-band dynamics processing effect to modify the audio coming out of Android devices and optimize it according to the preferences of the listener or the ambient conditions. Dynamics Processing API Take a look at the Android P features overview for a complete list of the new features and APIs.

Get started in a few simple steps

Android Virtual Device

First, make your app compatible and give your users a seamless transition to Android P. Just install your current app from Google Play on a Android P Beta device or emulator and test -- the app should run and look great, and handle Android P behavior change for all apps properly. After you've made any necessary updates, we recommend publishing to Google Play right away without changing the app's platform targeting.

If you don't have a supported device, remember that you can set up an Android Virtual Device on the Android Emulator as your test environment instead. If you haven't tried the emulator recently, you'll find that it's incredibly fast, boots in under 6 seconds, and even lets you model next-gen screens -- such as long screens and screens with display cutout.

Next, update your app's targetSdkVersion to 28 as soon as possible, so Android P users of your app can benefit from the platform's latest security, performance, and stability features. If your app is already targeting API 26+ in line with Google Play's upcoming policies, then changing to target 28 should be a small jump.

It's also important to test your apps for uses of non-SDK interfaces and reduce your reliance on them. As noted previously, in Android P we're starting a gradual process to restrict access to selected non-SDK interfaces. Watch for logcat warnings that highlight direct uses of restricted non-SDK interfaces and try the new StrictMode method detectNonSdkApiUsage() to catch accesses programmatically. Where possible, you should move to using public equivalents from the Android SDK or NDK. If there's no public API that meets your use-case, please let us know.

When you're ready, dive into Android P and learn about the new features and APIs to extend your apps. To build with the new APIs, just download the official API 28 SDK and tools into Android Studio 3.1, or use the latest version of Android Studio 3.2. Then update your project's compileSdkVersion and targetSdkVersion to API 28.

Visit the Developer Preview site for details and documentation. Also check out this video and the Google I/O Android playlist for more on what's new in Android P for developers.

Publish to Google Play alpha, beta, or production channels

Starting today you can publish your APK updates that are compiled against, or optionally targeting, API 28. Publishing an update to Google Play during the preview lets you push updates to users to test compatibility on existing devices, including devices running Android P Beta 2.

To make sure that your updated app runs well on Android P as well as older versions, a common strategy is to use Google Play's beta testing feature to get early feedback from a small group of users -- including Android P Beta 2 users — and then do a staged rollout to production.

How to get Android P Beta 2

For Pixel devices, you can enroll your device in the Android Beta program and you'll automatically receive the update to Android P Beta 2 over-the-air. If you're already enrolled and received Beta 1, watch for the update coming your way soon. Partners that are participating in the Android P Beta program will be updating their devices over the coming weeks.

You can see the full list of supported partner and Pixel devices at android.com/beta. For each device you'll find specs and links to the manufacturer's dedicated site for downloads, support, and to report issues.

Thanks for all of your feedback so far. Please continue to share feedback or requests as we work towards the consumer release later this summer. Feel free to use our hotlists for platform issues, app compatibility issues, and third-party SDK issues.

We're looking forward to seeing your apps on Android P!

Introducing new Android Excellence apps and games on Google Play

Kacey Fahey, Developer Marketing, Google Play

Congratulations to the latest apps and games featured in the Android Excellence program on Google Play. As a reminder, these collections are refreshed every three months and recognize apps and games that set the bar for high quality, great user experience, and strong technical performance.

If you're looking for some new apps, here are a few highlights.

  • Adobe Photoshop Lightroom CC: Capture, edit, and share your photos with the power of Lightroom on your mobile device. Use presets for quick and easy edits, or dive in with the advanced editing tools.
  • Seven - 7 Minute Workout Training Challenge: Use this app to fit seven minute workouts into your busy lifestyle. Grab your phone, or even your Wear OS device to work out anywhere and anytime. Keep it up to earn achievements and join the 7 Club for even more support.
  • SoloLearn: Learn to Code for Free: Learn one of many new coding languages by joining a community of millions. Tap in to the 24/7 peer support, or create your own lessons to become a community influencer.

Here are a few of our favorite new games joining the collection.

  • CodyCross: Crossword Puzzles: Try this game for a fun new style of crossword puzzles. Play for free on adventure mode or subscribe for special themed packs, varying difficulty levels and fresh content added weekly.
  • MARVEL Contest of Champions: Play with your favorite Marvel Super Heroes and Super Villians in iconic locations from the Marvel Universe. Assemble your team of champions to play through the exciting storyline and even build alliances with your friends.
  • Orbital 1: Test your skills in this real-time multiplayer game with beautiful 3D graphics. Collect and upgrade fighters and weapons to build out your perfect squad for quick battles and new daily quests.

See the full list of Android Excellence apps and games.

New Android Excellence apps New Android Excellence games
Adobe Photoshop Lightroom CC

Dashlane

Holstelworld

iCook

Keeper Password Manager

Keepsafe Photo Vault

Mobisystems OfficeSuite

PhotoGrid

Runtastic Results

Seven - 7 Minute Workout Training Challenge

SoloLearn: Learn to Code for Free

Tube Map

WPS Office

Angry Birds 2

Azur Lane アズールレーン

CodyCross

Into the Dead 2

Little Panda Restaurant

MARVEL Contest of Champions

Orbital 1

Rooms of Doom

Sky Dancer Run

Sling Kong

Soul Knight

Explore other great apps and games in the Editors' Choice section on Google Play and discover best practices to help you build quality apps and games.

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Cryptography Changes in Android P

Posted by Adam Vartanian, Software Engineer

We hope you're enjoying the first developer preview of Android P. We wanted to specifically call out some backward-incompatible changes we plan to make to the cryptographic capabilities in Android P, which you can see in the developer preview.

Changes to providers

Starting in Android P, we plan to deprecate some functionality from the BC provider that's duplicated by the AndroidOpenSSL (also known as Conscrypt) provider. This will only affect applications that specify the BC provider explicitly when calling getInstance() methods. To be clear, we aren't doing this because we are concerned about the security of the implementations from the BC provider, rather because having duplicated functionality imposes additional costs and risks while not providing much benefit.

If you don't specify a provider in your getInstance() calls, no changes are required.

If you specify the provider by name or by instance—for example, Cipher.getInstance("AES/CBC/PKCS7PADDING", "BC") or Cipher.getInstance("AES/CBC/PKCS7PADDING", Security.getProvider("BC"))—the behavior you get in Android P will depend on what API level your application targets. For apps targeting an API level before P, the call will return the BC implementation and log a warning in the application log. For apps targeting Android P or later, the call will throw NoSuchAlgorithmException.

To resolve this, you should stop specifying a provider and use the default implementation.

In a later Android release, we plan to remove the deprecated functionality from the BC provider entirely. Once removed, any call that requests that functionality from the BC provider (whether by name or instance) will throw NoSuchAlgorithmException.

Removal of the Crypto provider

In a previous post, we announced that the Crypto provider was deprecated beginning in Android Nougat. Since then, any request for the Crypto provider by an application targeting API 23 (Marshmallow) or before would succeed, but requests by applications targeting API 24 (Nougat) or later would fail. In Android P, we plan to remove the Crypto provider entirely. Once removed, any call to SecureRandom.getInstance("SHA1PRNG", "Crypto") will throw NoSuchProviderException. Please ensure your apps have been updated.

Previewing Android P

Posted by Dave Burke, VP of Engineering

Last week at Mobile World Congress we saw that Android's ecosystem of developers, device makers, and silicon partners continues to bring amazing experiences to users worldwide.

Looking ahead, today we're sharing the first developer preview of Android P, the newest version of Android. It's an early baseline build for developers only -- you're our most trusted reviewers and testers ;-) Early feedback from our developer community is crucial in helping us evolve the platform to meet your needs. We'd love to get you started exercising the new features and APIs in P, and as always, we depend on your early feedback and ideas, so please give us your input!

This first developer preview of Android P is just the start - we'll have lots more to share at Google I/O in May, stay tuned!

New features to try in your apps

Here's a look at some of the cool features in this first preview of Android P that we want you to try and give feedback on.

Indoor positioning with Wi-Fi RTT

Accurate indoor positioning has been a long-standing challenge that opens new opportunities for location-based services. Android P adds platform support for the IEEE 802.11mc WiFi protocol -- also known as WiFi Round-Trip-Time (RTT) -- to let you take advantage of indoor positioning in your apps.

On Android P devices with hardware support, location permission, and location enabled, your apps can use RTT APIs to measure the distance to nearby WiFi Access Points (APs). The device doesn't need to connect to the APs to use RTT, and to maintain privacy, only the phone is able to determine the distance, not the APs.

Knowing the distance to 3 or more APs, you can calculate the device position with an accuracy of 1 to 2 meters. With this accuracy, you can build new experiences like in-building navigation; fine-grained location-based services such as disambiguated voice control (e.g.,'Turn on this light'); and location-based information (e.g., 'Are there special offers for this product?').

Display cutout support

Now apps can take full advantage of the latest device screens with fullscreen content. We've added display cutout into the platform, along with APIs that you can use to manage how your content is displayed.

Cutout support works seamlessly for apps, with the system managing status bar height to separate your content from the cutout. If you have critical, immersive content, you can also use new APIs to check the cutout shape and request full-screen layout around it. You can check whether the current device has a cutout by calling getDisplayCutout(), and then determine the location and shape of the cutout area using DisplayCutout. A new window layout attribute, layoutInDisplayCutoutMode, lets you tell the system how and when lay out your content relative to the cutout area. Details are here.

To make it easier to build and test cutout support in your app, we've added a Developer Option that simulates a cutout on any device. We recommend testing your existing apps with display cutout enabled to ensure that your content displays properly.

Apps with immersive content can display content fullscreen on devices with a display cutout.

Improved messaging notifications

In Android P we've put a priority on improving visibility and function in notifications. Try the new MessagingStyle notification style -- it highlights who is messaging and how you can reply. You can show conversations, attach photos and stickers, and even suggest smart replies. See the details here.

In MessagingStyle notifications you can now show conversations and smart replies [left] and even attach images and stickers [right].

Multi-camera API

You can now access streams simultaneously from two or more physical cameras on devices running Android P. On devices with either dual-front or dual-back cameras, you can create innovative features not possible with just a single camera, such as seamless zoom, bokeh, and stereo vision. The API also lets you call a logical or fused camera stream that automatically switches between two or more cameras. We're looking forward to seeing your new and exciting creations as Android P devices supporting multiple cameras reach the market in the year ahead.

Other improvements in camera include new Session parameters that help to reduce delays during initial capture, and Surface sharing that lets camera clients handle various use-cases without the need to stop and start camera streaming. We've also added APIs for display-based flash support and access to OIS timestamps for app-level image stabilization and special effects.

ImageDecoder for bitmaps and drawables

Android P gives you an easier way to decode images to bitmaps or drawables -- ImageDecoder, which deprecates BitmapFactory. ImageDecoder lets you create a bitmap or drawable from a byte buffer, file, or URI. It offers several advantages over BitmapFactory, including support for exact scaling, single-step decoding to hardware memory, support for post-processing in decode, and decoding of animated images.

You can decode and scale to an exact size just by calling setResize() with the target dimensions. You can also call getSampledSize() to get the image dimensions at a specific sample rate, then scale to those dimensions. If you want post-process an image -- such as applying rounded corners for circle masks or more complicated effects -- you can pass ImageDecoder any android.graphics.PostProcessor. You can also create Drawables directly, with ImageDecoder.decodeDrawable(). If the encoded image is an animated GIF or WebP, the Drawable will be an instance of the new AnimatedImageDrawable.

HDR VP9 Video, HEIF image compression, and Media APIs

Android P adds built-in support for HDR VP9 Profile 2, so you can now deliver HDR-enabled movies to your users from YouTube, Play Movies, and other sources on HDR-capable devices.

We're excited to add HEIF (heic) image encoding to the platform. HEIF is a popular format for photos that improves compression to save on storage and network data. With platform support on Android P devices, it's easy to send and utilize HEIF images from your backend server. Once you've made sure that your app is compatible with this data format for sharing and display, give HEIF a try as an image storage format in your app. You can do a jpeg-to-heic conversion using ImageDecoder or BitmapFactory to obtain a bitmap from jpeg, and you can use HeifWriter in the new Support Library alpha to write HEIF still images from YUV byte buffer, Surface, or Bitmap.

We're also in the process of enhancing and refactoring the media APIs to make them easier to develop and integrate with -- watch for details coming later this year.

Data cost sensitivity in JobScheduler

JobScheduler is Android's central service to help you manage scheduled tasks or work across Doze, App Standby, and Background Limits changes. In Android P, JobScheduler handles network-related jobs better for the user, coordinating with network status signals provided separately by carriers.

Jobs can now declare their estimated data size, signal prefetching, and specify detailed network requirements—carriers can report networks as being congested or unmetered. JobScheduler then manages work according to the network status. For example, when a network is congested, JobScheduler might defer large network requests. When unmetered, it can run prefetch jobs to improve the user experience, such as by prefetching headlines.

When you are adding jobs, try using setEstimatedNetworkBytes(), setIsPrefetch() and setRequiredNetwork() to let JobScheduler handle the work properly. When your job executes, be sure to use the Network object returned by JobParameters.getNetwork(), otherwise you'll implicitly use the device's default network which may not meet your requirements, causing unintended data usage.

Neural Networks API 1.1

We introduced the Neural Networks API in Android 8.1 to accelerate on-device machine learning on Android. In Android P we're expanding and improving this API, adding support for nine new ops -- Pad, BatchToSpaceND, SpaceToBatchND, Transpose, Strided Slice, Mean, Div, Sub, and Squeeze. If you have a Pixel 2 device, the DP1 build now includes an Qualcomm Hexagon HVX driver with acceleration for quantized models.

Autofill improvements

In Android P we're continuing to improve the Autofill Framework based on feedback from users and developers. Along with key bugfixes, this release includes new APIs that allow password managers to improve the Autofill user experience, such as better dataset filtering, input sanitization, and compatibility mode. Compatibility mode in particular has a high impact on end users because it lets password managers take the accessibility-based approach in apps that don't yet have full Autofill support, but without impacts on performance or security. See all the details on what's new here.

Open Mobile API for NFC payments and secure transactions

Android P adds an implementation of the GlobalPlatform Open Mobile API to Android. On supported devices, apps can use the OMAPI API to access secure elements (SE) to enable smart-card payments and other secure services. A hardware abstraction layer (HAL) provides the underlying API for enumerating a variety of Secure Elements (eSE, UICC, and others) available.

Strengthening Android's foundations

In Android P we're continuing our long-term investment to make Android the best platform for developers.

Security for apps

In Android P we're moving to a more consistent UI for fingerprint authentication across apps and devices. Android now provides a standard system dialog to prompt the user to touch the fingerprint sensor, managing text and placement as appropriate for the device. Apps can trigger the system fingerprint dialog using a new FingerprintDialog API. We recommend switching to the new system dialog as soon as possible.

As part of a larger effort to move all network traffic away from cleartext (unencrypted HTTP) to TLS, we're also changing the defaults for Network Security Configuration to block all cleartext traffic. If you are using a Network Security Configuration, you'll now need to make connections over TLS, unless you explicitly opt-in to cleartext for specific domains.

Privacy for users

To better ensure privacy, Android P restricts access to mic, camera, and all SensorManager sensors from apps that are idle. While your app's UID is idle, the mic reports empty audio and sensors stop reporting events. Cameras used by your app are disconnected and will generate an error if the app tries to use them. In most cases, these restrictions should not introduce new issues for existing apps, but we recommend removing these requests from your apps.

We will also enable encryption of Android backups with a client-side secret. This feature is still in active development and will be launched in a future Android P preview release.

Longer term we're working to bring support for per-network randomization of associated MAC addresses to the platform. On supported devices running Android P, you can enable this experimentally for testing as a new developer option.

Android P also gives the user control over access to the platform's build.serial identifier by putting it behind the READ_PHONE_STATE permission. Direct access to this identifier has been deprecated since Android 8.0. In order to access the build.serial identifier, you should use the Build.getSerial() method.

ART performance

We're working to bringing performance and efficiency improvements to all apps through the ART runtime. We've expanded ART's use of execution profiles to optimize apps and reduce in-memory footprint of compiled app code. ART now uses profile information for on-device rewriting of DEX files, with reductions up to 11% across a range of popular apps. We expect these to correlate closely with reductions in system DEX memory usage and faster startup times for your apps.

Optimized Kotlin

Kotlin is a first-class language on Android, and if you haven't tried it yet, you should! We've made an enduring commitment to Kotlin in Android and continue to expand support including optimizing the performance of Kotlin code. In P you'll see the first results of this work -- we've improved several compiler optimizations, especially those that target loops, to extract better performance. We're also continuing to work in partnership with JetBrains to optimize Kotlin's generated code. You can get all of the latest Kotlin performance improvements just by keeping Android Studio's Kotlin plugin up-to-date.

Power efficiency

In Android P we continue to refine Doze, App Standby, and Background Limits to further improve battery life; please be sure to try your apps with these and send feedback.

Targeting modern Android

Android P is shaped by our longer-term initiatives to modernize the foundations of Android and the apps that run on it. As we announced recently, Google Play will require all app updates to target Android Oreo (targetSdkVersion 26 or higher) by November 2018, with support for 64-bit hardware on the horizon for 2019.

In line with these changes, Android P will warn users with a dialog when they install an app that targets a platform earlier than Android 4.2 (targetSdkVersion less than 17), and future platform versions will continue to increment that lower bound. We're encouraging every Android developer to start planning the migration to target API 26 now, and to start the migration work as soon as possible. Here's a checklist of resources for help and support -- we're looking forward to seeing your apps getting the most from modern Android.

Improving app compatibility through public APIs

A key issue for users and developers is app compatibility -- making sure that apps are ready for new platform versions as they arrive, without risk of crashes for users and emergency rollouts for developers. Apps that use Android's public APIs from the SDK or NDK are in a good position to be compatible, but apps that use private Android interfaces and libraries are not.

So with Android P we're starting a gradual process to restrict access to selected non-SDK interfaces, asking developers -- including app teams inside Google -- to use the public equivalents instead. In cases where there is no public equivalent for your use-case, please let us know -- we want to make sure that this process is as smooth as possible for developers, so we'll use your feedback to ensure the initial rollout only affects APIs where developers can easily migrate to public alternatives. More about the restrictions is here.

Get started in a few simple steps

First, make your app compatible to give your users a seamless transition to Android P. Just download a device system image or emulator system image, install your current app, and test -- the app should run and look great, and handle behavior changes properly. After you've made any necessary updates, we recommend publishing to Google Play right away without changing the app's platform targeting.

Remember, you don't need a supported Pixel device to test or develop on Android P. For most uses we highly recommend setting up an Android Virtual Device on the Android Emulator as a test environment instead. If you haven't tried the emulator recently, you'll find that it's incredibly fast , boots in under 6 seconds, convenient to use, and you can even model next-gen screens -- such as long screens and screens with camera cutout.

Next, change your app's targeting to "P" and run it with the full Android P experience. Set your app's targetSdkVersion to 'P' and compileSdkVersion to android-P, build, and test. Make sure to read the behavior changes for apps targeting P to find areas you will want to test and might need to adjust.

When you're ready, dive into Android P and learn about the many new features and APIs you can take advantage of in your app. To make it easier to explore the new APIs, take a look at the API diff report, along with the Android P API reference. Visit the P Developer Preview site for details on the preview timeline and support resources. Also check out this video highlighting what's new in Android P for developers.

To get started building with Android P, download the P Developer Preview SDK and tools into Android Studio 3.1 or use the latest Android Studio 3.2 canary version. We're also releasing an alpha version of the 28.0.0 support library for you to try.

What's ahead?

The Android P Developer Preview includes an updated SDK with system images for testing on the official Android Emulator and on Pixel, Pixel XL Pixel 2, and Pixel 2 XL devices.

We plan to update the preview system images and SDK regularly throughout the preview. This initial release is for developers only and not intended for daily or consumer use, so we're making it available by manual download and flash only. Downloads and instructions are here.

As we get closer to a final product, we'll be inviting consumers to try it out as well, and we'll open up enrollments through Android Beta at that time. Stay tuned for details, but for now please note that Android Beta is not currently available for Android P.

As always, your feedback is critical, so please let us know what you think — the sooner we hear from you, the more of your feedback we can integrate. When you find issues, please report them here. We have separate hotlists for filing platform issues, app compatibility issues, and third-party SDK issues.