Tag Archives: notifications

First preview of Android 12

Android 12 logo

Posted by Dave Burke, VP of Engineering

Every day, Android apps help billions of people work, play, communicate, and create on a wide range of devices from phones and laptops to tablets, TVs, and cars. As more people come to rely on the experiences you build, their expectations can rise just as fast. It’s one of the reasons we share Android releases with you early: your feedback helps us build a better platform for your apps and all of the people who use them. Today, we’re releasing the first Developer Preview of Android 12, the next version of Android, for your testing and feedback.

With each version, we’re working to make the OS smarter, easier to use, and better performing, with privacy and security at the core. In Android 12 we’re also working to give you new tools for building great experiences for users. Starting with things like compatible media transcoding, which helps your app to work with the latest video formats if you don’t already support them, and easier copy/paste of rich content into your apps, like images and videos. We’re also adding privacy protections and optimizing performance to keep your apps responsive.

Today’s first preview is just the start for Android 12, and we’ll have lots more to share as we move through the release. Read on for a taste of what’s new in Android 12, and visit the Android 12 developer site for details on downloads for Pixel and release timeline. As always, it’s crucial to get your feedback early, to help us incorporate it into the final product, so let us know what you think!

Alongside the work we’re doing in Android 12, later this month we’ll have more to share on another important tool that helps you create great user experiences more easily: Jetpack Compose, our modern toolkit for building native UI. Join us on #TheAndroidShow for a behind-the-scenes look at Jetpack Compose, livestreamed on February 24 at 9AM PT, and tweet your Jetpack Compose questions using #TheAndroidShow to have them answered live on the show.

Trust and safety

Privacy is at the heart of everything we do, and in Android 12 we’re continuing to focus on giving users more transparency and control while keeping their devices and data secure. In today’s release we’ve added new controls over identifiers that can be used for tracking, safer defaults for app components, and more. These changes may affect your apps, so we recommend testing as soon as possible. Watch for more privacy and security features coming in later preview releases.

Modern SameSite cookie behaviors in WebView - In line with changes to Chrome and other browsers, WebView includes new SameSite cookie behaviors to provide additional security and privacy and give users more transparency and control over how cookies can be used across sites. More here.

Restricted Netlink MAC - We’re continuing to help developers migrate to privacy-protecting resettable identifiers. In a multi-release effort to ease migration of device-scoped Netlink MAC, in Android 11 we restricted access to it based on API level 30, and in Android 12 we’re applying the restriction for all apps - regardless of targetSDK level. More here.

Safer exporting of components - To prevent apps from inadvertently exporting activities, services, and receivers, we’re changing the default handling of the android:exported attribute to be more explicit. With this change, components that declare one or more intent filters must now explicitly declare an android:exported attribute. You should inspect your components in the manifest in order to avoid installation errors related to this change. More here.

Safer handling of Intents - To make handling PendingIntents more secure, Android 12 requires apps to explicitly declare a mutability flag, either FLAG_MUTABLE or the new FLAG_IMMUTABLE, for each PendingIntent. More here.

You can read more about these and other privacy and security changes here.

Better user experience tools

In Android 12 we’re investing in key areas to help deliver a polished experience and better performance for users. Here are some of the updates so far.

Compatible media transcoding - With the prevalence of HEVC hardware encoders on mobile devices, camera apps are increasingly capturing in HEVC format, which offers significant improvements in quality and compression over older codecs. Most apps should support HEVC, but for apps that can’t, we’re introducing compatible media transcoding.

With this feature, an app that doesn’t support HEVC can have the platform automatically transcode the file into AVC, a format that is widely compatible. The transcoding process takes time, depending on the video and hardware properties of the device. As an example, a one minute 1080p video at 30fps takes around 9 seconds to transcode on a Pixel 4. You can opt-in to use the transcoding service by just declaring the media formats that your apps don't support. For developers, we strongly recommend that your apps support HEVC, and if that’s not possible, enable compatible media transcoding. The feature will be active on all devices using HEVC format for video capture. We'd love to hear your feedback on this feature. More here.

AVIF image support - To give you higher image quality with more efficient compression, Android 12 introduces platform support for AV1 Image File Format (AVIF). AVIF is a container format for images and sequences of images encoded using AV1. Like other modern image formats, AVIF takes advantage of the intra-frame encoded content from video compression. This dramatically improves image quality for the same file size when compared to older image formats, such as JPEG.

AVIF (18.2kB)

JPEG (20.7kB)

race car photo in AVIF (18.2kB)
race car photo in JPEG (20.7kB)

Credit: Image comparison from AVIF has landed by Jake Archibald

Foreground service optimizations - Foreground services are an important way for apps to manage certain types of user-facing tasks, but when overused they can affect performance and even lead to app kills. To ensure a better experience for users, we will be blocking foreground service starts from the background for apps that are targeting the new platform. To make it easier to transition away from this pattern, we’re introducing a new expedited job in JobScheduler that gets elevated process priority, network access, and runs immediately regardless of power constraints like Battery Saver or Doze. For back-compatibility, we’ve also built expedited jobs into the latest release of Jetpack WorkManager library. Also, to reduce distraction for users, we’re now delaying the display of some foreground service notifications by up to 10 seconds. This gives short-lived tasks a chance to complete before their notifications are shown. More here.

Rich content insertion - Users love images, videos and other expressive content, but inserting and moving this content in apps is not always easy. To make it simple for your apps to receive rich content, we’re introducing a new unified API that lets you accept content from any source: clipboard, keyboard, or drag and drop. You can attach a new interface, OnReceiveContentListener, to UI components and get a callback when content is inserted through any mechanism. This callback becomes the single place for your code to handle insertion of all content, from plain and styled text to markup, images, videos, audio files, and more. For back-compatibility, we’ve added the unified API to AndroidX. More here.

Haptic-coupled audio effect - In Android 12 apps can provide audio-coupled haptic feedback through the phone's vibrator. The vibration strength and frequency are derived from an audio session, allowing you to create more immersive game and audio experiences. For example, a video calling app could use custom ringtones to identify the caller through haptic feedback, or you could simulate rough terrain in a racing game. More here.

Multi-channel audio - Android 12 includes several enhancements for audio with spatial information. It adds support for MPEG-H playback in passthrough and offload mode, and the audio mixers, resamplers and effects have been optimized for up to 24 channels (the previous maximum was 8).

Immersive mode API improvements for gesture nav - We’ve simplified immersive mode so that gesture navigation is easier and more consistent, for example when watching a video, reading a book, or playing a game. We’re still protecting apps from accidental gestures when in full-screen experiences related to gaming, but in all other full-screen or immersive experiences (e.g. video viewers, reading, photo gallery), for apps targeting the new platform, we’re changing the default to allow users to navigate their phone with one swipe. More here.

Notification UI updates - We’re refreshing notification designs to make them more modern, easier to use, and more functional. In this first preview you’ll notice changes from the drawer and controls to the templates themselves. We’re also optimizing transitions and animations across the system to make them more smooth. As part of the updates, for apps targeting Android 12 we’re decorating notifications with custom content with icon and expand affordances to match all other notifications. More here.

Faster, more responsive notifications - When users tap a notification, they expect to jump immediately into the app - the faster the better. To meet that expectation, developers should make sure that notification taps trigger Activity starts directly, rather than using “trampolines” - an intermediary broadcast receiver or service - to start the Activity. Notification trampolines can cause significant delays and affect the user experience. To keep notifications responsive, Android 12 will block notification trampolines by preventing them from launching their target Activities, and we’re asking developers to migrate away from this pattern. The change applies only to apps targeting the new platform, but for all apps we’ll display a toast to make trampolines visible to you and to users. More here.

Improved Binder IPC calls - As part of our work on performance, we’ve put a focus on reducing system variability. We’ve taken a look at latency and workload distribution, and made optimizations that reduce the median experience from the tail end, or 99% percentile use case. In doing so, we’ve targeted improvements to system binder calls adding lightweight caching strategies and focusing on removing lock contention to improve latency distribution. This has yielded roughly a 2x performance increase on Binder calls overall, with significant improvements in specific calls, for example a 47x improvement in refContentProvider(), 15x in releaseWakeLock(), and 7.9x in JobScheduler.schedule().

App compatibility

We’re working to make updates faster and smoother by prioritizing app compatibility as we roll out new platform versions. In Android 12 we’ve made most app-facing changes opt-in to give you more time, and we’ve updated our tools and processes to help you get ready sooner. We’ve also added new functionality to Google Play system updates to give your apps a better environment on Android 12 devices.

More of Android updated through Google Play - We’re continuing to expand our investment in Google Play system updates (Project Mainline) to give apps a more consistent, secure environment across devices. In Android 12 we’ve added the Android Runtime (ART) module that lets us push updates to the core runtime and libraries on devices running Android 12. We can improve runtime performance and correctness, manage memory more efficiently, and make Kotlin operations faster - all without requiring a full system update. We’ve also expanded the functionality of existing modules - for example, we’re delivering our compatible media transcoding feature inside an updatable module.

Optimizing for tablets, foldables, and TVs - With more people than ever using apps on large-screen devices like foldables, tablets, and TVs, now is a great time to make sure your app or game is ready. Get started by optimizing for tablets and building apps for foldables. And, for the biggest screen in the home, the first Android 12 preview for Android TV is also available. In addition to bringing the latest Android features to the TV with this preview, you will also be able to test your apps on the all-new Google TV experience. Learn more on the Android TV Developers site and get started with your ADT-3 developer kit.

Updated lists of non-SDK interfaces - We’ve restricted additional non-SDK interfaces, and as always your feedback and requests for public API equivalents are welcome.

Easier testing and debugging of changes - To make it easier for you to test the opt-in changes that can affect your app, we’ve made many of them toggleable. WIth the toggles you can force-enable or disable the changes individually from Developer options or adb. Check out the details here.

mobile display of App Compatibility Changes with toggles

App compatibility toggles in Developer Options.

Platform stability milestone - Like last year, we’re letting you know our Platform Stability milestone well in advance, to give you more time to plan for app compatibility work. At this milestone we’ll deliver not only final SDK/NDK APIs, but also final internal APIs and app-facing system behaviors. We’re expecting to reach Platform Stability by August 2021, and you’ll have several weeks before the official release to do your final testing. The release timeline details are here.

Get started with Android 12

The Developer Preview has everything you need to try the Android 12 features, test your apps, and give us feedback. You can get started today by flashing a device system image to a Pixel 3 / 3 XL, Pixel 3a / 3a XL, Pixel 4 / 4 XL, Pixel 4a / 4a 5G, or Pixel 5 device. If you don’t have a Pixel device, you can use the 64-bit system images with the Android Emulator in Android Studio.

When you’re set up, here are some of the things you should do:

  • Try the new features and APIs - your feedback is critical during the early part of the developer preview. Report issues in our tracker or give us direct feedback by survey for selected features from the feedback and requests page.
  • Test your current app for compatibility - the goal here is to learn whether your app is affected by default behavior changes in Android 12. Just install your current published app onto a device or emulator running Android 12 and test.
  • Test your app with opt-in changes - Android 12 has opt-in behavior changes that only affect your app when it’s targeting the new platform. It’s extremely important to understand and assess these changes early. To make it easier to test, you can toggle the changes on and off individually.

We’ll update the preview system images and SDK regularly throughout the Android 12 release cycle. This initial preview release is for developers only and not intended for daily or consumer use, so we're making it available by manual download only. You can flash a factory image to your Pixel device, or you can sideload an OTA image to a Pixel device running Android 11, in which case you won’t need to unlock your bootloader or wipe data. Either way, once you’ve manually installed a preview build, you’ll automatically get future updates over-the-air for all later previews and Betas. More 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 12.

For complete information, visit the Android 12 developer site.

Turning it up to 11: Android 11 for developers

Posted by Stephanie Cuthbertson, Director, Product Management

Android 11 logo

Android 11 is here! Today we’re pushing the source to the Android Open Source Project (AOSP) and officially releasing the newest version of Android. We built Android 11 with a focus on three themes: a People-centric approach to communication, Controls to let users quickly get to and control all of their smart devices, and Privacy to give users more ways to control how data on devices is shared. Read more in our Keyword post.

For developers, Android 11 has a ton of new capabilities. You’ll want to check out conversation notifications, device and media controls, one-time permissions, enhanced 5G support, IME transitions, and so much more. To help you work and develop faster, we also added new tools like compatibility toggles, ADB incremental installs, app exit reasons API, data access auditing API, Kotlin nullability annotations, and many others. We worked to make Android 11 a great release for you, and we can’t wait to see what you’ll build!

Watch for official Android 11 coming to a device near you, starting today with Pixel 2, 3, 3a, 4, and 4a devices. To get started, visit the Android 11 developer site.

People, Controls, Privacy

People

Android 11 is people-centric and expressive, reimagining the way we have conversations on our phones, and building an OS that can recognize and prioritize the most important people in our lives. For developers, Android 11 helps you build deeper conversational and personal interactions into your apps.

  • Conversation notifications appear in a dedicated section at the top of the shade, with a people-forward design and conversation specific actions, such as opening the conversation as a bubble, creating a conversation shortcut on the home screen, or setting a reminder.
  • Bubbles - Bubbles help users keep conversations in view and accessible while multitasking on their devices. Messaging and chat apps should use the Bubbles API on notifications to enable this in Android 11.
  • Consolidated keyboard suggestions let Autofill apps and Input Method Editors (IMEs) securely offer users context-specific entities and strings directly in an IME’s suggestion strip, where they are most convenient for users.
mobile display of conversation UI

Bubbles and people-centric conversations.

Controls

Android 11 lets users quickly get to and control all of their smart devices in one space. Developers can use new APIs to help users surface smart devices and control media:

  • Device Controls make it faster and easier than ever for users to access and control their connected devices. Now, by simply long pressing the power button, they’re able to bring up device controls instantly, and in one place. Apps can use a new API to appear in the controls. More here.
  • Media Controls make it quick and convenient for users to switch the output device for their audio or video content, whether it be headphones, speakers or even their TV. More here.
Device controls on mobile device Media controls on mobile device

Device controls and media controls.

Privacy

In Android 11, we’re giving users even more control and transparency over sensitive permissions and working to keep devices more secure through faster updates.

One-time permission - Now users can give an app access to the device microphone, camera, or location, just for one time. The app can request permissions again the next time the app is used. More here.

Permission notification

One-time permission dialog in Android 11.

Background location - Background location now requires additional steps from the user beyond granting a runtime permission. If your app needs background location, the system will ensure that you first ask for foreground location. You can then broaden your access to background location through a separate permission request, and the system will take the user to Settings to complete the permission grant.

Also note that in February we announced that Google Play developers will need to get approval to access background location in their app to prevent misuse. We're giving developers more time to make changes and won't be enforcing the policy for existing apps until 2021.

Permissions auto-reset - if users haven’t used an app for an extended period of time, Android 11 will “auto-reset” all of the runtime permissions associated with the app and notify the user. The app can request the permissions again the next time the app is used. More here.

Scoped storage - We’ve continued our work to better protect app and user data on external storage, and made further improvements to help developers more easily migrate. More here.

Google Play system updates - Launched last year, Google Play system updates help us expedite updates of core OS components to devices in the Android ecosystem. In Android 11, we more than doubled the number of updatable modules, including 12 new modules that will help improve privacy, security, and consistency for users and developers.

BiometricPrompt API - Developers can now use the BiometricPrompt API to specify the biometric authenticator strength required by their app to unlock or access sensitive parts of the app. For backward compatibility, we’ve just added these capabilities to the Jetpack Biometric library. We’ll share further updates as the work progresses.

Identity Credential API - This will unlock new use cases such as mobile drivers licences, National ID, and Digital ID. We’re working with various government agencies and industry partners to make sure that Android 11 is ready for digital-first identity experiences.

You can read about all of the Android 11 privacy features here.

Helpful innovation

Enhanced 5G support - Android 11 includes updated developer support to help you take advantage of the faster speeds and lower latency of 5G networks. You can learn when the user is connected to a 5G network, check whether the connection is metered, and get an estimate of the connection bandwidth. To help you build experiences now for 5G, we’ve also added 5G support in the Android Emulator. To get started with 5G on Android, visit the 5G developer page.

image of Google Maps on mobile

Moving beyond the home, 5G can for example let you enhance your “on-the-go” experience by providing seamless interactions with the world around you from friends and family to businesses.

New screen types - Device makers are continuing to innovate by bringing exciting new device screens to market, such as hole-punch and waterfall screens. Android 11 adds support for these in the platform, with APIs to let you optimize your apps. You can manage both hole-punch and waterfall screens using the existing display cutout APIs. You can set a new window layout attribute to use the entire waterfall screen, and a new waterfall insets API helps you manage interaction near the edges.

Call screening support - Android 11 helps call-screening apps do more to manage robocalls. Apps can verify an incoming call’s STIR/SHAKEN status (standards that protect against caller ID spoofing) as part of the call details, and they can report a call rejection reason. Apps can also customize a system-provided post call screen to let users perform actions such as marking a call as spam or adding to contacts.

Polish and quality

OS resiliency - In Android 11 we’ve made the OS more dynamic and resilient as a whole by fine-tuning memory reclaiming processes, such as forcing user-imperceptible restarts of processes based on RSS HWM thresholds. Also, to improve performance and memory, Android 11 adds Binder caching, which optimizes highly used IPC calls to system services by caching data for those that retrieve relatively static data. Binder caching also improves battery life by reducing CPU time.

Synchronized IME transitions - New APIs let you synchronize your app’s content with the IME (input method editor, or on-screen keyboard) and system bars as they animate on and offscreen, making it much easier to create natural, intuitive and jank-free IME transitions. For frame-perfect transitions, a new WindowInsetsAnimation.Callback API notifies apps of per-frame changes to insets while the system bars or the IME animate. Additionally, you can use a new WindowInsetsAnimationController API to control system UI types like system bars, IME, immersive mode, and others. More here.

Synchronized IME transition through insets animation listener. App-driven IME experience through WindowInsetsAnimationController.

Synchronized IME transition through insets animation listener.

App-driven IME experience through WindowInsetsAnimationController.

HEIF animated drawables - The ImageDecoder API now lets you decode and render image sequence animations stored in HEIF files, so you can make use of high-quality assets while minimizing impact on network data and APK size. HEIF image sequences can offer drastic file-size reductions for image sequences when compared to animated GIFs.

Native image decoder - New NDK APIs let apps decode and encode images (such as JPEG, PNG, WebP) from native code for graphics or post processing, while retaining a smaller APK size since you don’t need to bundle an external library. The native decoder also takes advantage of Android’s process for ongoing platform security updates. See the NDK sample code for examples of how to use the APIs.

Low-latency video decoding in MediaCodec - Low latency video is critical for real-time video streaming apps and services like Stadia. Video codecs that support low latency playback return the first frame of the stream as quickly as possible after decoding starts. Apps can use new APIs to check and configure low-latency playback for a specific codec.

Variable refresh rate - Apps and games can use a new API to set a preferred frame rate for their windows. Most Android devices refresh the display at 60Hz refresh rate, but some support multiple refresh rates, such as 90Hz as well as 60Hz, with runtime switching. On these devices, the system uses the app’s preferred frame rate to choose the best refresh rate for the app. The API is available in both the SDK and NDK. See the details here.

Dynamic resource loader - Android 11 includes a new public API to let apps load resources and assets dynamically at runtime. With the Resource Loader framework you can include a base set of resources in your app or game and then load additional resources, or modify the loaded resources, as needed at runtime.

Neural Networks API (NNAPI) 1.3 - We continue to add ops and controls to support machine learning on Android devices. To optimize common use-cases, NNAPI 1.3 adds APIs for priority and timeout, memory domains, and asynchronous command queue. New ops for advanced models include signed integer asymmetric quantization, branching and loops, and a hard-swish op that helps accelerate next-generation on-device vision models such as MobileNetV3.

Developer friendliness

App compatibility tools - We worked to minimize compatibility impacts on your apps by making most Android 11 behavior changes opt-in, so they won’t take effect until you change the apps’ targetSdkVersion to 30. If you are distributing through Google Play, you’ll have more than a year to opt-in to these changes, but we recommend getting started testing early. To help you test, Android 11 lets you enable or disable many of the opt-in changes individually. More here.

App exit reasons - When your app exits, it’s important to understand why the app exited and what the state was at the time -- across the many device types, memory configurations, and user scenarios that your app runs in. Android 11 makes this easier with an exit reasons API that you can use to request details of the app’s recent exits.

Data access auditing - data access auditing lets you instrument your app to better understand how it accesses user data and from which user flows. For example, it can help you identify any inadvertent access to private data in your own code or within any SDKs you might be using. More here.

ADB Incremental - Installing very large APKs with ADB (Android Debug Bridge) during development can be slow and impact your productivity, especially those developers working on Android Games. With ADB Incremental in Android 11, installing large APKs (2GB+) from your development computer to an Android 11 device is up to 10x faster. More here.

Kotlin nullability annotations - Android 11 adds nullability annotations to more methods in the public API. And, it upgrades a number of existing annotations from warnings to errors. These help you catch nullability issues at build time, rather than at runtime. More here.

Get your apps ready for Android 11

With Android 11 on its way to users, now is the time to finish your compatibility testing and publish your updates.

Flow chart steps for getting your apps ready for Android 11.

Here are some of the top behavior changes to watch for (these apply regardless of your app’s targetSdkVersion):

  • One-time permission - Users can now grant single-use permission to access location, device microphone and camera. More here.
  • External storage access - Apps can no longer access other apps’ files in external storage. More here.
  • Scudo hardened allocator - Scudo is now the heap memory allocator for native code in apps. More here.
  • File descriptor sanitizer - Fdsan is now enabled by default to detect file descriptor handling issues for native code in apps. More here.

Android 11 also includes opt-in behavior changes - these affect your app once it’s targeting the new platform. We recommend assessing these changes as soon as you’ve published the compatible version of your app. For more information on compatibility testing and tools, check out the resources we shared for Android 11 Compatibility week and visit the Android 11 developer site for technical details.

Enhance your app with new features and APIs

Next, when you're ready, dive into Android 11 and learn about the new features and APIs that you can use. Here are some of the top features to get started with.

We recommend these for all apps:

  • Dark theme (from Android 10) - Make sure to provide a consistent experience for users who enable system-wide dark theme by adding a Dark theme or enabling Force Dark.
  • Gesture navigation (from Android 10) - Support gesture navigation by going edge-to-edge and ensure that custom gestures work well with gestures. More here.
  • Sharing shortcuts (from Android 10) - Apps that want to receive shared data should use the sharing shortcuts APIs to create share targets. Apps that want to send shared data should make sure to use the system share sheet.
  • Synchronized IME transitions - Provide seamless transitions to your users using the new WindowInsets and related APIs. More here.
  • New screen types - for devices with hole-punch or waterfall screens, make sure to test and adjust your content for these screens as needed. More here.

We recommend these if relevant for your app:

  • Conversations - Messaging and communication apps can participate in the conversation experience by providing long-lived sharing shortcuts and surfacing conversations in notifications. More here.
  • Bubbles - Bubbles are a way to keep conversations in view and accessible while multitasking. Use the Bubbles API on notifications to enable this.
  • 5G - If your app or content can benefit from the faster speeds and lower latency of 5G, explore our developer resources to see what you can build.
  • Device controls - If your app supports external smart devices, make sure those devices are accessible from the new Android 11 device controls area. More here.
  • Media controls - For media apps, we recommend supporting the Android 11 media controls so users can manage playback and resumption from the Quick Settings shade. More here.

Read more about all of the Android 11 features at developer.android.com/11.

Coming to a device near you!

Android 11 will begin rolling out today on select Pixel, OnePlus, Xiaomi, OPPO and realme phones, with more partners launching and upgrading devices over the coming months. If you have a Pixel 2, 3, 3a, 4, or 4a phone, including those enrolled in this year’s Beta program, watch for the over-the-air update arriving soon!

Android 11 factory system images for Pixel devices are also available through the Android Flash Tool, or you can download them here. As always, you can get the latest Android Emulator system images via the SDK Manager in Android Studio. For broader testing on other Treble-compliant devices, Generic System Images (GSI) are available here.

If you're looking for the Android 11 source code, you'll find it here in the Android Open Source Project repository under the Android 11 branches.

What’s next?

We’ll soon be closing the preview issue tracker and retiring open bugs logged against Developer Preview or Beta builds, but please keep the feedback coming! If you still see an issue that you filed in the preview tracker, just file a new issue against Android 11 in the AOSP issue tracker.

Thanks again to the many developers and early adopters who participated in the preview program this year! You gave us great feedback to help shape the release, and you filed thousands of issues that have made Android 11 a better platform for everyone.

We're looking forward to seeing your apps on Android 11!

Getting screen brightness right for every user

Posted by Ben Murdoch, Software Engineer and Michael Wright, Android Framework Engineer

The screen on a mobile device is critical to the user experience. The improved Adaptive Brightness feature in Android P automatically manages the display to match your preferences for brightness level so you get the best experience, whatever the current lighting environment.

Screen brightness in Android is managed via Quick Settings or via the settings app

(Settings → Display → Brightness Level).

In Android Pie, Adaptive Brightness is enabled by default (Settings → Display → Adaptive Brightness).

While enabled, Android automatically selects a screen brightness that's suitable for the user's current ambient light conditions. Prior to Android Pie, the brightness slider didn't represent an absolute screen brightness level, but a global adjustment factor for boosting or reducing the device manufacturer's preset screen brightness curve across all ambient light levels:

* Setting the slider to center resulted in the device using the preset.

* Setting the slider to the left of center applied a negative scale factor, making the screen dimmer than the preset.

* Setting the slider to the right of center applied a positive scale factor, making the screen brighter than the preset.

So, under low ambient light conditions, you might prefer a brighter screen than the preset level and move the brightness slider up accordingly. But, because that adjustment would boost the brightness at all ambient light levels, you might find yourself needing to move the brightness slider back down in brighter ambient light. And so on, back and forth.

To improve this experience, we've introduced two important changes to screen brightness in Android Pie:

  1. Better slider control
  2. Personalization of the brightness level

Better slider control

The slider control now represents absolute screen brightness rather than the global adjustment factor. That means that you may see it move on its own while Adaptive Brightness is on. This is expected behavior!

Humans perceive brightness on a logarithmic rather than linear scale1. That means changes in screen brightness are much more noticeable when the screen is dark versus bright. To match this difference in perception, we updated the brightness slider UI in the notification shade and System Settings app to work on a more human-like scale. This means you may need to move the slider farther to the right than you did on previous versions of Android for the same absolute screen brightness, and that when setting a dark screen brightness you have more precise control over exactly which brightness to set.

Personalization of screen brightness

Prior to Android P, when developing a new Android device the device manufacturer would determine a baseline mapping from ambient brightness to screen brightness based on the display manufacturer's recommendation and a bit of experimentation. All users of that device would receive the same baseline mapping and, while using the device, move the brightness slider around to set their global adjustment factor. To determine the final screen brightness, the system would first look at the room brightness and the baseline mapping to find the default screen brightness for that situation, and then apply the global adjustment factor.

What we found is that in many cases this global adjustment factor didn't adequately capture personal preferences - that is, users tended to change the slider often for new lighting environments.

For Android Pie we worked with researchers from DeepMind to build a machine learning model that will observe the interactions that a user makes with the screen brightness slider, and train on-device to personalise the mapping of ambient light level to screen brightness.

This means that Android will learn what screen brightness is comfortable for a user in a given lighting environment. The user teaches it by manually adjusting the slider, and, as the software trains over time, the user should need to make fewer manual adjustments. In testing the feature, we've observed that after a week almost half our test users are making fewer manual adjustments while the total number of slider interactions across all internal test users was reduced by over 10%. The model that we've developed is updatable and will be tuned based on real world usage now that Android Pie has been released. This means that the model will continue to get better over time.

We believe that screen brightness is one of those things that should just work, and these changes in Android Pie are a step towards realizing that. For the best performance no matter where you are models run directly on the device rather than the cloud, and train overnight while the device charges.

The improved Adaptive Brightness feature is now available on Pixel devices and we are working with our OEM partners now to incorporate Adaptive Brightness into Android Pie builds for their devices.

Notes

Discontinuing support for Android Nearby Notifications

Posted by Ritesh Nayak M, Product Manager

Three years ago, we created Nearby Notifications as a way for Android users to discover apps and content based on what is nearby. Our goal was to bring relevant and engaging content to users - to provide useful information proactively. Developers have leveraged this technology to let users know about free wifi nearby, provide guides while in a museum, and list transit schedules at bus stops.

We've learned a lot building and launching Nearby Notifications. However, earlier this year, we noticed a significant increase in locally irrelevant and spammy notifications that were leading to a poor user experience. While filtering and tuning can help, in the end, we have a very high bar for the quality of content that we deliver to users, especially content that is delivered through notifications. Ultimately, we have determined these notifications did not meet that bar. As a result, we have decided to discontinue support for Nearby Notifications. We will stop serving Nearby Notifications on December 6th, 2018.

What does it mean for Android users

Android users will stop receiving Nearby Notifications.

What does it mean for developers

On December 6th we will stop delivering both Eddystone and Physical Web beacon notifications. You will still continue to have access to the beacon dashboard and can deliver proximity based experiences similar to Nearby Notifications via your own apps using our Proximity Beacons API.

We have two related APIs, Nearby Messages and Connections, that are available for developers to build device-to-device connectivity experiences, and also have Fast Pair, for device discovery and pairing. We will continue to invest in these APIs and support products using these technologies.

We sincerely appreciate the efforts of the Android developer community in supporting and evolving Nearby technology and the feedback that has helped us improve. We look forward to continuing to deliver engaging proximity experiences to users and seeing what developers create within their apps with our APIs.

What’s New in Android: O Developer Preview 2 & More

Posted by: Dave Burke, VP of Engineering

android-o-logo.png
With billions of Android devices around the world, Android has surpassed our wildest expectations. Today at Google I/O, we showcased a number of ways we’re pushing Android forward, with the O Release, new tools for developers to help create more performant apps, and an early preview of a project we call Android Go -- a new experience that we’re building for entry-level devices.
Fluid experiences in Android O
It's pretty incredible what you can do on mobile devices today, and how easy it is to rely on them as computers in our pockets. In the O release we've focused on creating fluid experiences that make Android even more powerful and easy to use, and today we highlighted some of those:
  • Picture-in-picture: lets users manage two tasks simultaneously, whether it’s video calling your friend while checking your calendar, or reading a new recipe while watching a video on a specific cooking technique. We’ve designed PIP to provide seamless multitasking on any size screen, and it’s easy for apps to support it.
  • Notification dots extend the reach of notifications, a new way for developers to surface activity in their app, driving engagement. Built on our unique and highly regarded notification system, dots work with zero effort for most apps - we even extract the color of the dot from your icon. 
  • Autofill with Google simplifies setting up a new device and synchronizing passwords by bringing Chrome's Autofill feature to Android. Once a user opts-in, Autofill will work out-of-the-box for most apps. Developers can optimize their apps for Autofill by providing hints about the type of data expected or add support in custom views. 
  • A new homescreen for Android TV makes it easy for users to find, preview, and watch content provided by apps. Apps can publish one or more channels, and users can control the channels that appear on the homescreen. You’ll be able to get started with creating channels using the new TvProvider support library APIs
  • Smart Text Selection: In Android O, we’re applying on-device machine learning to copy/paste, to let Android recognize entities like addresses, URLs, telephone numbers, and email addresses. This makes the copy/paste experience better by selecting the entire entity and surfacing the right apps to carry out an action based on the type of entity.
  • TensorFlow Lite: As Android continues to take advantage of machine learning to improve the user experience, we want our developer partners to be able to do the same. Today we shared an early look at TensorFlow Lite, an upcoming project based on TensorFlow, Google’s open source machine learning library. TensorFlow Lite is specifically designed to be fast and lightweight for embedded use cases. Since many on-device scenarios require real-time performance, we’re also working on a new Neural Network API that TensorFlow can take advantage of to accelerate computation. We plan to make both of these available to developers in a maintenance update to O later this year, so stay tuned!  
(L) Android O: Picture-in-picture, (R) Android O: Notification dots

Working on the Vitals in Android
We think Android’s foundations are critical, so we’re investing in Android Vitals, a project focused on optimizing battery life, startup time, graphic rendering time, and stability. Today we showcased some of the work we’ve done so far, and introduced new tools to help developers understand power, performance, and reliability issues in their apps:
  • System optimizations: in Android O, we’ve done a lot of work across the system to make apps run faster and smoother. For example we made extensive changes in our runtime - including new optimizations like concurrent compacting garbage collection, code locality, and more. 
  • Background limits: up to now it’s been fairly easy for apps to unintentionally overuse resources while they’re in the background, and this can adversely affect the performance of the system. So in O, we've introduced new limits on background location and wi-fi scans, and changes in the way apps run in the background. These boundaries prevent overuse -- they’re about increasing battery life and freeing up memory.
  • New Android Vitals Dashboards in the Play Console: today we launched six Play Console dashboards to help you pinpoint common issues in your apps - excessive crash rate, ANR rate, frozen frames, slow rendering, excessive wakeups, and stuck wake locks, including how many users are affected, with guidance on the best way to address the issues. You can visit the Play Console today to see your app's data, then learn how to address any issues.
Android Go
Part of Android’s mission is to bring computing to everyone. We’re excited about seeing more users come online for the first time as the price of entry level smart phones drop, and we want to help manufacturers continue to offer lower-cost devices that provide a great experience for these users. Today we gave a sneak peek of a new experience that we’re building specifically for Android devices that have 1GB or less of memory -- Internally we call it “Android Go,” and it’s designed around three things
  • OS: We’re optimizing Android O to run smoothly and efficiently on entry-level devices
  • Apps: We’re also designing Google apps to use less memory, storage space, and mobile data, including apps such as YouTube Go, Chrome, and Gboard. 
  • Play: On entry-level devices, Play store will promote a better user experience by highlighting apps that are specifically designed for these devices -- such as apps that use less memory, storage space, and mobile data -- while still giving users access to the entire app catalog.
The Android Go experience will ship in 2018 for all Android devices that have 1GB or less of memory. We recommend getting your apps ready for these devices soon -- take a look at the Building for Billions to learn about the importance of offering a useful offline state, reducing APK size, and minimizing battery and memory use.

O Developer Preview 2, Now in Public Beta
Today’s release of O Developer Preview 2 is our first beta-quality candidate, available to test on your primary phone or tablet. We’re inviting those who want to try the beta release of Android O to enroll now at android.com/beta -- it’s an incredibly convenient way to preview Android O on your Nexus 5X, 6P, and Player, as well as Pixel, Pixel XL, or Pixel C device.

With more users starting to get Android O on their devices through the Android Beta program, now is the time to test your apps for compatibility, resolve any issues, and publish an update as soon as possible. See the migration guide for steps and a recommended timeline.

Later today you’ll be able to download the updated tools for developing on Android O, including the latest canaries of Android Studio, SDK, and tools, Android O system images, and emulators. Along with those, you’ll be able to download support library 26.0.0 beta and other libraries from our new Maven repo. The change to Maven from SDK Manager means a slight change to your build configuration, but gives you much more flexibility in how you integrate library updates with your CI systems.

When you’re ready to get started developing with Android O, visit the O Developer Preview site for details on all of the features you can use in your apps, including notification channels and dots, picture-in-picture, autofill, and others. APIs have changed since the first developer preview, so take a look at the diff report to see where your code might be affected.

Thanks for the feedback you’ve given us so far. Please keep it coming, about Android O features, APIs, issues, or requests -- see the Feedback and Bugs page for details on where to report feedback.

Engaging users during major events: How The Guardian used innovative notifications

Posted By Tamzin Taylor, Partner Development at Google Play

Major sporting, cultural, political events present an opportunity to re-engage users if you can find a relevant and unique way to serve them information. For example, The Guardian was able to substantially increase user engagement with its mobile app during the recent US election by using new notifications functionality in Android 7.0 Nougat. While notifications themselves are nothing new, The Guardian used innovative techniques and design elements to give their users a rich, real time update on the election results as they happened.
How The Guardian innovated with notifications

Users who opted-in received a single, continuously updating notification which was persistent on their lock screen as results came in on election night. The notification used avatars of the candidates and a progress bar to bring the information to life.




The notification showed the most up-to-date numbers of electoral votes won and states called, an indication of which swing states have been called, and the breakdown of the popular vote between the two leading candidates.

"Having the ability to have a constantly updating notification on screen, allowed us to keep our users engaged throughout election night".
– Rob Phillips from The Guardian

Another important feature was the ability to notify users of major updates with a link to detailed information and analysis. In order to do this, the Guardian allowed the newsroom teams to push notifications of major events, such as when the 270 vote mark was passed.

"Our newsroom could let our readers know in real time when there was a serious milestone, and we were able to deliver 101 unique notifications during the course of the evening. The clear menu options acted as key drivers to our journalism as the news unfolded, and meant we could get our readers connected with our content when they were most receptive".
– Rob Phillips from The Guardian
Results and next steps
The engagement results were impressive:
  • 170K people signed up to see the alert, with 122K users interacting with the alert
  • The average number of interactions was around 620K, or 5.1 per user
  • 74% of users who saw the notification tapped through to the main live blog
  • 25% of users who saw the notification tapped through to our full results content
Finally, perhaps the most impressive statistic is that promoting live updates (via the notification) resulted in 103% increase in daily installs during election week.

"By providing our users with the ability to quickly and easily check information, to highlight major moments and to direct people to where to find more information, we can deliver value to our readers, helping them make sense of the events wherever they are, quickly and succinctly. After all, that's what we're here to do as a news company, and we're delighted that the new functionality on Nougat lets us do that"
– Rob Phillips from The Guardian

On the back of the success of using Android N capabilities for live notifications, the Guardian plans to test the same approach with sports content, and explore how it could be applied more extensively to other major events like The Oscars and the Super Bowl.


How useful did you find this blogpost?
                                                                              

A Google Santa Tracker update from Santa’s Elves

Sam Thorogood, Developer Programs Engineer

Today, we're announcing that the open source version of Google's Santa Tracker has been updated with the Android and web experiences that ran in December 2015. We extended, enhanced and upgraded our code, and you can see how we used our developer products - including Firebase and Polymer - to build a fun, educational and engaging experience.

To get started, you can check out the code on GitHub at google/santa-tracker-weband google/santa-tracker-android. Both repositories include instructions so you can build your own version.

Santa Tracker isn’t just about watching Santa’s progress as he delivers presents on December 24. Visitors can also have fun with the winter-inspired experiences, games and educational content by exploring Santa's Village while Santa prepares for his big journey throughout the holidays.

Below is a summary of what we’ve released as open source.

Android app

  • The Santa Tracker Android app is a single APK, supporting all devices, such as phones, tablets and TVs, running Ice Cream Sandwich (4.0) and up. The source code for the app can be found here.
  • Santa Tracker leverages Firebase features, including Remote Config API, App Invites to invite your friends to play along, and Firebase Analytics to help our elves better understand users of the app.
  • Santa’s Village is a launcher for videos, games and the tracker that responds well to multiple devices such as phones and tablets. There's even an alternative launcher based on the Leanback user interface for Android TVs.

  • Games on Santa Tracker Android are built using many technologies such as JBox2D (gumball game), Android view hierarchy (memory match game) and OpenGL with special rendering engine (jetpack game). We've also included a holiday-themed variation of Pie Noon, a fun game that works on Android TV, your phone, and inside Google Cardboard's VR.

Android Wear

  • The custom watch faces on Android Wear provide a personalized touch. Having Santa or one of his friendly elves tell the time brings a smile to all. Building custom watch faces is a lot of fun but providing a performant, battery friendly watch face requires certain considerations. The watch face source code can be found here.
  • Santa Tracker uses notifications to let users know when Santa has started his journey. The notifications are further enhanced to provide a great experience on wearables using custom backgrounds and actions that deep link into the app.

On the web

  • Santa Tracker is mobile-first: this year's experience was built for the mobile web, including an amazing brand new, interactive - yet fully responsive, village: with three breakpoints, touch gesture support and support for the Web App Manifest.
  • To help us develop Santa at scale, we've upgraded to Polymer 1.0+. Santa Tracker's use of Polymer demonstrates how easy it is to package code into reusable components. Every housein Santa's Village is a custom element, only loaded when needed, minimizing the startup cost of Santa Tracker.

  • Many of the amazing new games (like Present Bounce) were built with the latest JavaScript standards (ES6) and are compiled to support older browsers via the Google Closure Compiler.
  • Santa Tracker's interactive and fun experience is enhanced using the Web Animations API, a standardized JavaScript APIfor unifying animated content.
  • We simplified the Chromecast support this year, focusing on a great screensaver that would countdown to the big event on December 24th - and occasionally autoplay some of the great video content from around Santa's Village.

We hope that this update inspires you to make your own magical experiences based on all the interesting and exciting components that came together to make Santa Tracker!

Get the Do’s and Don’ts for Notifications from Game Developer Seriously

Posted by Lily Sheringham, Developer Marketing at Google Play

Editor’s note: We’ve been talking to developers to find out how they’ve been achieving success on Google Play. We recently spoke to Reko Ukko at Finnish mobile game developer, Seriously, to find out how to successfully use Notifications.

Notifications on Android let you send timely, relevant, and actionable information to your users' devices. When used correctly, notifications can increase the value of your app or game and drive ongoing engagement.

Seriously is a Finnish mobile game developer focused on creating entertaining games with quality user experiences. They use push notifications to drive engagement with their players, such as helping players progress to the next level when they’ve left the app after getting stuck.

Reko Ukko, VP of Game Design at Seriously, shared his tips with us on how to use notifications to increase the value of your game and drive ongoing engagement.

Do’s and don’ts for successful game notifications

Do’s

Don’ts

Do let the user get familiar with your service and its benefits before asking for permission to send notifications.

Don’t treat your users as if they’re all the same - identify and group them so you can push notifications that are relevant to their actions within your app.

Do include actionable context. If it looks like a player is stuck on a level, send them a tip to encourage action.

Don’t spam push notifications or interrupt game play. Get an understanding of the right frequency for your audience to fit the game.

Do consider re-activation. If the player thoroughly completes a game loop and could be interested in playing again, think about using a notification. Look at timing this shortly after the player exits the game.

Don’t just target players at all hours of the day. Choose moments when players typically play games – early morning commutes, lunch breaks, the end of the work day, and in the evening before sleeping. Take time zones into account.

Do deep link from the notification to where the user expects to go to based on the message. For example. if the notification is about "do action X in the game now to win", link to where that action can take place.

Don’t forget to expire the notifications if they’re time-limited or associated with an event. You can also recycle the same notification ID to avoid stacking notifications for the user.

Do try to make an emotional connection with the player by reflecting the style, characters, and atmosphere of your game in the notification. If the player is emotionally connected to your game, they’ll appreciate your notifications and be more likely to engage.

Don’t leave notifications up to guess work. Experiment with A/B testing and iterate to compare how different notifications affect engagement and user behavior in your app. Go beyond measuring app opening metrics – identify and respond to user behavior.

Experiment with notifications yourself to understand what’s best for your players and your game. You can power your own notifications with Google Cloud Messaging, which is free, cross platform, reliable, and thoughtful about battery usage. Find out more about developing Notifications on Android.

A new reference app for multi-device applications

It is now possible to bring the benefits of your app to your users wherever they happen to be, no matter what device they have near them. Today we’re releasing a reference sample that shows how to implement such a service with an app that works across multiple Android form-factors. This sample, the Universal Music Player, is a bare-bones but functional reference app that supports multiple devices and form factors in a single codebase. It is compatible with Android Auto, Android Wear, and Google Cast devices. Give it a try and easily adapt your own app for wherever your users are, be that a phone, watch, TV, car, or more!

Playback controls and album art in the lock screen.
On the application toolbar, the Google Cast icon.

screendump-2015-03-09-16:23:54.png
Controlling playback through Android Auto


Controlling playback on an Android Wear watch

This sample uses a number of new features in Android 5.0 Lollipop, like MediaStyle notifications, MediaSession and MediaBrowserService. They make it easy to implement media browsing and playback on multiple devices with a single version of your app.

Check out the source code and let your users enjoy your app from wherever they like.

Posted by Renato Mangini, Senior Developer Platform Engineer, Google Developer Platform Team

The Guardian — Understanding and engaging mobile users

Posted by Leticia Lago, Google Play team

The Guardian is a global news organization with one of the world's largest quality English-speaking news websites, theguardian.com. It has more than 100 million monthly unique browsers and app users, two thirds of which come from outside the UK. With a longstanding reputation for agenda-setting journalism, the publication is most recently renowned for its Pulitzer Prize and Emmy-winning coverage of the disclosures made by whistleblower Edward Snowden. The Guardian’s early adoption of a digital-first policy and continued digital innovation means it has also become a respected name among developers and tech audiences. In the last year, it has launched a redesigned app and new website and been among a handful of publishers to develop its own Glassware.

The Guardian app is taking advantage of unique Google Play and Android features to drive user engagement. Their mobile app readers are now 10 to 20 times more engaged than their average web users. Improving engagement has also helped them lift the rating for their app from 4.0 to 4.4 on Google Play.

Anthony Sullivan, Director of Product, and Tom Grinsted, Product Manager, share some best practices for increasing app engagement in this video.

To learn more, be sure to check out these resources to better engage your users:

  • Convert installs to active users [video] — hear from Matteo Vallone, Partner Development Manager for Google Play, about the best practices for engaging and retaining users through intents, identity, context, and rich notifications as well as delivering a cross-platform user experience.
  • Adding Wearable Features to Notifications [tutorial] — learn how to add notifications to Android Wear devices, including how to make use of the Wear notification features: voice commands, stacks, and pages.
  • Beta testing [help] — discover how to make use of the alpha and beta testing features offered by Google Play, and get feedback from real users.
  • Build your community (of testers) [guide] — get advice on how to build communities on G+ or other social networks, then tap into their skills and enthusiasm to help with testing your app.