Author Archives: Android Developers

New! Android Kotlin codelab courses are here

Posted by Jocelyn Becker, Senior Program Manager, Google Developer Training

Want to learn to build Android apps in Kotlin? Get started with the Kotlin Bootcamp for Programmers and Developing Android apps in Kotlin codelabs courses.

Google and Udacity currently offer video-based courses for Kotlin Bootcamp and How to build Android apps in Kotlin. To help people that learn in different ways, we have recently reworked these courses to publish them as tutorial-based codelab courses. More than 2.5 million users have worked through Google codelabs like this just this year.

Kotlin Bootcamp

Google provides first class support for building Android apps in Kotlin, including Kotlin-friendly Android APIs and API extensions. Kotlin fully interoperates with the Java programming language and libraries, and is included with IntelliJ and Android Studio.

In the Kotlin Bootcamp course, you will learn everything you need to program in Kotlin, beginning with the basics such as how to write Kotlin statements, and working up to functional manipulation such as extending builtin functions.

If you already know how to program, the Kotlin Bootcamp provides the foundation you'll need to build Android apps in Kotlin.

Start the Kotlin Bootcamp now!

Building Android apps in Kotlin

When you feel comfortable with Kotlin, you can dive right into building Android apps. This course takes you from "Hello World" to connecting with the world. You start building a basic interactive user interface on one screen, and end with a multi-screen Google Developer Group (GDG) Finder app that gets data from a live server on the internet. In between, you learn about Android Jetpack components, such as Room for databases, Work Manager for background processing, the Navigation component, and more. You'll use popular community libraries to simplify common tasks, such as Glide for image loading, Retrofit for networking, and Moshi for JSON parsing. The course teaches key Kotlin features such as coroutines to help you write your app code more quickly and concisely.

In each lesson, you will work with a realistically architected app and implement key features. For example, you start out learning how to deploy a dice roller app. You learn how to implement navigation by building the "Android Trivia" game. You learn how to create a Room database by building a sleep tracker app.

Overall, you will create and work with more than 10 apps, so, by the end of this course, you will have a portfolio of example code that you can use to realize your own amazing app ideas!

Get started now!

Expand your app beyond mobile to reach Android users at large

Posted by Sameer Samat, Vice President, Platforms & Ecosystems

dark theme graphic illustration with geometric shapes and Android 2019 logo

From day one, we designed Android to be a flexible, adaptive platform.

Most people picture a smartphone when they think of Android, but Android also powers an amazing number of large-screen devices. In fact, there are more than 175 million Android tablets with the Google Play store,1 making Android tablets a vital form factor for Google and our OEM partners today. Android apps also run on Chrome OS laptops, and the number of monthly active users who enabled Android apps grew 250% in just the last year.2

Here at Google, we’re excited to see how you can take advantage of large-screen formats - including Samsung’s new Galaxy Tab S6, the upcoming Lenovo™ Smart Tab M8 with Google Assistant, the upcoming Samsung Fold, and other devices launching this week at IFA. Our OEM partners are building experiences that help users every day:

image of two quotes

From the start, Android was designed as a platform that could handle multiple screen sizes. Over the years, we’ve continued to add functionality for developers to accommodate new devices and form factors.

  • We started with a phone. Developers could write Android apps that would work on phones of all sizes, all over the world. Part of what made this work was Android’s resource and layout system, which enabled applications to smoothly adapt to different screen sizes.
  • In Android 3.0 Honeycomb, we added support for tablets. In particular, capabilities like Fragments allow you to create applications that work across vastly different form factors.
  • Android 7 Nougat brought multi-window and multi-display capabilities, including the ability to drag-and-drop across apps. Meanwhile, Chrome OS added the capability to run Android applications on laptops. With some adjustments to handle different inputs and windowing dynamics, you could now reach app users in a desktop-style environment.
Android’s layout system helps applications smoothly resize and adjust their layout interactively.

Android’s layout system helps applications smoothly resize and adjust their layout interactively.

  • Now, in Android 10, we’ve made even more enhancements for development on large screens. We’ve improved multi-window capabilities, making it easier to use multiple apps in parallel. We also continued improving multi-display support, enabling more multi-monitor use cases. And we made it easy for you to experiment and test new form factors by adding dedicated emulator for foldables as well as publishing a foldables guide.

By optimizing your app to take advantage of different form factors, developers have an opportunity to deliver richer, more engaging experiences to millions of users on larger screens. And if you don’t have access to physical devices, the Android Emulator supports all of the form factors mentioned above, from Chrome OS to phones and tablets.


Developers of apps like Mint, Evernote, and Asphalt are just a few who have seen success from taking their existing APK to larger screens.

image of a single quote from Damien Marchi, VP of Marketing at Gameloft

To learn more about optimizing your Android apps for richer experiences on tablets, Chrome OS laptops, foldables, and more, join us at the Android Developer Summit on October 23-24 — either in person or via the livestream — or check out our recap videos on YouTube.

Sources:

[1] The number of tablets only accounts for devices that have the Google Play Store installed (for example, this excludes tablets in China); the actual number of tablets capable of running Android applications is much larger.

[2] Google Internal Data, March 2018 to March 2019.

Welcoming Android 10!

Posted by Stephanie Cuthbertson, Senior Director of Product Management, Android

After more than a year of development and months of testing by early adopters, we’re ready to introduce Android 10 to the world!

android 10 logo

Android 10 is built around three important themes. First, Android 10 is shaping the leading edge of mobile innovation with advanced machine-learning and support for emerging devices like foldables and 5G enabled phones. Next, Android 10 has a central focus on privacy and security, with almost 50 features that give users greater protection, transparency, and control. Finally, Android 10 expands users' digital wellbeing controls so individuals and families can find a better balance with technology.

Today we're releasing the Android 10 source code to Android Open Source Project (AOSP) and making it available to the broader ecosystem. We’re also starting the official Android 10 rollout to all three generations of Pixel devices worldwide. Many partner devices, including those in the Beta program, will receive the update by the end of the year.

Thank you for your support during this year’s Beta -- more than 200,000 of you tested early releases on 26 different Beta devices, reporting 20,000 unique issues. That’s on top of the many articles, discussions, surveys, and in-person meetings where you voiced your thoughts, and the work you did to make your apps compatible by today’s release. Your support and engagement are what make Android such an amazing platform. Together with our OEM partners you’ve created more excitement for this Android release than we’ve ever had. In fact, Android 10 will be available on more devices than any other previous release. Android is fortunate to have such a passionate community!

To get started developing for Android 10, visit developer.android.com/10.

What’s in Android 10?

Here’s a look at what’s in Android 10 and how you can use it today. Make sure to check out our Keyword blog for more too!

Innovation and new experiences

With Android 10 you can take advantage of the latest hardware and software innovations to build amazing app experiences for users.

Foldables - Building on robust multi-window support, Android 10 extends multitasking across app windows and provides screen continuity to maintain your app state as the device folds or unfolds. For details on how to optimize your apps for foldables, see the developer guide.

5G networks promise to deliver consistently faster speeds and lower latency, and Android 10 adds platform support for 5G and extends existing APIs to help you take advantage of these enhancements. You can use connectivity APIs to detect if the device has a high bandwidth connection and check whether the connection is metered. With these, your apps and games can tailor rich, immersive experiences to users over 5G.

Live Caption automatically captions media playing on users’ devices, from videos to podcasts and audio messages, across any app. The ML speech models run right on the phone, and no audio stream ever leaves the device. For developers, Live Caption is optional, but expands the audience for your apps and games by making your content more accessible with a single tap. Live Caption is coming to Pixel devices this fall, and we’re working closely with our partners to launch it broadly on devices running Android 10.

Smart Reply in notifications - Android 10 uses on-device ML to suggest contextual actions in notifications, such as smart replies for messages or opening a map for an address in the notification. We’ve built this feature with user privacy in mind, keeping the ML processing completely on the device. Your apps can take advantage of this feature right away, or you can opt-out if you’d rather generate your own suggestions.

mobile displaying Smart Reply notification

Smart Reply can suggest actions based on notification content.

Dark theme - Android 10 adds a system-wide dark theme that’s ideal for low light and helps save battery. You can build a custom dark theme for your app or let the system create one dynamically from your current theme. See the developer guide for details.

Dark theme to do lists

Dark theme in Google Keep

Gesture navigation - Android 10 introduces a fully gesture navigation mode that eliminates the navigation bar area and allows apps to use the full screen to deliver richer, more immersive experiences. Get started optimizing your app today.

gesture gif displaying closing of full screen map to display dinner with Layla in 30 min

Gesture navigation gives apps the full screen for content

Privacy for users

Privacy is a central focus in Android 10, from stronger protections in the platform to new features designed with privacy in mind. Building on previous releases, Android 10 includes extensive changes to protect privacy and give users control, with improved system UI, stricter permissions, and restrictions on what data apps can use. See the Android 10 developer site for details on how to support these in your apps.

Giving users more control over location data - Users have more control over their location data through a new permission option -- they can now allow an app to access location only while the app is actually in use (running in the foreground). For most apps this provides a sufficient level of access, while for users it’s a big improvement in transparency and control. To learn more about location changes, see the developer guide or our blog post.

notification displaying: Allow app 1 to access the device's location.

Protecting location data in network scans - Most of the APIs for scanning networks already required the coarse location permission. Android 10 increases the protection around those APIs by requiring the fine location permission instead.

Preventing device tracking - Apps can no longer access non-resettable device identifiers that could be used for tracking, including device IMEI, serial number, and similar identifiers. The device's MAC address is also randomized when connected to Wi-Fi networks by default. Read the best practices to help you choose the right identifiers for your use case, and see the details here.

Securing user data in external storage - Android 10 introduces a number of changes to give users more control over files in external storage and the app data within them. Apps can store their own files in their private sandboxes, but must use MediaStore to access shared media files and use the system file picker to access shared files in the new Downloads collection. Learn more here.

Blocking unwanted interruptions - Android 10 prevents app launches from the background that unexpectedly jump into the foreground and take over focus from another app. Learn more here.

Security

On Android we’re always working to assess our ongoing security investments; we refer to this as measurable security. One way we measure our ongoing investments is through third party analyst research such as Gartner’s May 2019 Mobile OSs and Device Security: A Comparison of Platforms report (subscription required) which scored Android the highest possible rating in 26 out of 30 categories, ahead on multiple points from authentication to network security and malware protection. Read more about our long-term work on Security in Quantifying Measurable Security. But there is no finish line when it comes to Security. In Android 10, we’ve introduced even more features to keep users secure through advances in encryption, platform hardening, and authentication.

Storage encryption - All compatible devices launching with Android 10 are required to encrypt user data, and to make this more efficient, Android 10 includes Adiantum, our new encryption mode.

TLS 1.3 by default - Android 10 also enables TLS 1.3 by default, a major revision to the TLS standard with performance benefits and enhanced security.

Platform hardening - Android 10 also includes hardening for several security-critical areas of the platform, and updates to the BiometricPrompt framework with robust support for face and fingerprint in both implicit and explicit authentication. Read more about Android 10 security updates here.

Camera and media

Dynamic depth for photos - Apps can now request a Dynamic Depth image, which consists of a JPEG, XMP metadata related to depth related elements, and a depth and confidence map embedded in the same file. These let you offer specialized blurs and bokeh options in your app. Dynamic Depth is an open format for the ecosystem and we're working with our partners to bring it to devices running Android 10 and later.

image of a shaggy dog's profile with patio furniture in the background image of a shaggy dog's profile with patio furniture blurred out in the background. image of a shaggy dog's profile in grayscale and blurred out

With Dynamic Depth image you can offer specialized blurs and bokeh options in your app

Audio playback capture - Now any app that plays audio can let other apps capture its audio stream using a new audio playback capture API. In addition to enabling captioning and subtitles, the API lets you support popular use-cases like live-streaming games. We’ve built this new capability with privacy and copyright protection in mind, so the ability for an app to capture another app's audio is constrained. Read more in our blog post.

New audio and video codecs - Android 10 adds support for the open source video codec AV1, which allows media providers to stream high quality video content to Android devices using less bandwidth. In addition, Android 10 supports audio encoding using Opus - an open, royalty-free codec optimized for speech and music streaming, and HDR10+ for high dynamic range video on devices that support it.

Native MIDI API - For apps that perform their audio processing in C++, Android 10 introduces a native MIDI API to communicate with MIDI devices through the NDK. This API allows MIDI data to be retrieved inside an audio callback using a non-blocking read, enabling low latency processing of MIDI messages. Give it a try with the sample app and source code here.

Vulkan everywhere - Vulkan 1.1 is now a requirement on all 64-bit devices running Android 10 and higher, and a recommendation for all 32-bit devices. We already see significant momentum on Vulkan support in the ecosystem - among devices running Android N or above, over half support Vulkan 1.0.3 or better. With the new requirement in Android 10, we expect to see adoption rise even further in the coming year.

Connectivity

Improved peer-to-peer and internet connectivity - We’ve refactored the Wi-Fi stack to improve privacy and performance, and also to improve common use-cases like managing IoT devices and suggesting internet connections -- without requiring the location permission. The network connection APIs make it easier to manage IoT devices over local Wi-Fi, for peer-to-peer functions like configuring, downloading, or printing. The network suggestion APIs let apps surface preferred Wi-Fi networks to the user for internet connectivity.

Wi-Fi performance modes - Apps can now request adaptive Wi-Fi by enabling high performance and low latency modes. These can be a great benefit where low latency is important to the user experience, such as real-time gaming, active voice calls, and similar use-cases. The platform works with the device firmware to meet the requirement with the lowest power consumption.

Android foundations

ART optimizations - Improvements in the ART runtime help your apps start faster, consume less memory, and run smoother -- without requiring any work from you. ART profiles delivered by Google Play let ART pre-compile parts of your app even before it's run. At runtime, Generational Garbage Collection makes garbage collection more efficient in terms of time and CPU, reduces jank, and helps apps run better on lower-end devices.

Startup time improvement - Profiles in Play bar chart

This chart shows the percentage improvement in startup time for specific apps when tested using Play profiles.

Neural Networks API 1.2 - We’ve added 60 new operations including ARGMAX, ARGMIN, quantized LSTM, alongside a range of performance optimizations. This lays the foundation for accelerating a much greater range of models -- such as those for object detection and image segmentation. We’re working with hardware vendors and popular machine learning frameworks such as TensorFlow to optimize and roll out support for NNAPI 1.2.

Faster updates, fresher code

With Android 10 we’re continuing our focus on bringing the new platform to devices more rapidly, working closely with our device-makers and silicon partners like Qualcomm. Project Treble has played a key role, helping us bring 18 partner devices into this year’s Beta program along with 8 Pixel devices -- more than double the number from last year. Even better, we expect those devices to get the official Android 10 update by the end of this year, and we’re working with several partners on other new flagship launches and updates. We’re seeing great momentum with Android 10 already, and more devices than any other previous Android release will be getting this new version in the months ahead.

Android 10 is also the first release to support Project Mainline (officially called Google Play system updates), our new technology for securing Android users and keeping their devices fresh with important code changes - direct from Google Play. With Google Play system updates, we’re able to update specific internal components across all devices running Android 10 and higher, without requiring a full system update from the device manufacturer. We’re expecting to bring the first updates to consumer devices over the next several months.

For developers, we expect these updates in Android 10 to help drive consistency of platform implementation broadly across devices, and over time bring greater uniformity that will reduce your development and testing costs.

Get your apps ready for Android 10!

Now with today’s public release of Android 10 and updates coming soon to devices, we’re asking all Android developers to update your current apps for compatibility as soon as possible to give your users a smooth transition to Android 10.

Here’s how to do it:

  • Install your app on Android 10: Install your current app from Google Play onto a Pixel or other device running Android 10 or an emulator, then test. Your app should look great and run well, with full functionality, and handle all of the Android 10 behavior changes properly. Watch for impacts from privacy changes, gesture navigation, changes to dynamic linker paths for Bionic libraries, and others.
  • Test with the Android 10 privacy features, such as the new location permissions, scoped storage, restrictions on background activity starts, changes to data and identifiers, and others. See the checklist of top privacy changes to get started, and review the privacy changes doc for more areas to test.
  • Test for uses of restricted non-SDK interfaces and move to public SDK or NDK equivalents instead. Details here.
  • Test the libraries and SDKs in your app: If you find an issue, try updating to the latest version of the SDK, or reach out to the SDK developer for help.
  • Update and publish your compatible app: When you’ve finished your testing and made any updates, we recommend publishing your compatible app right away. This helps you deliver a smooth transition to users as they update to Android 10.

Getting apps tested and ready for the new version of Android is crucial to faster platform updates throughout the ecosystem, so please prioritize this work if possible.

Enhance your app with Android 10 features and APIs

Next, when you're ready, dive into Android 10 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 every app:

  • Dark Theme: Ensure a consistent experience for users who enable system-wide dark theme by adding a Dark Theme or enabling Force Dark.
  • Gesture navigation: Support gesture navigation in your app by going edge-to-edge and making sure your custom gestures are complementary to the system navigation gestures.
  • Optimize for foldables: Deliver seamless experiences on today’s innovative devices by optimizing for foldables.

We recommend these if relevant for your app:

  • More interactive notifications: If your notifications include messages, enable Smart Reply in notifications to engage users and let them take action instantly.
  • Better biometrics: If you use biometric auth, move to BiometricPrompt, the preferred way to support fingerprint auth on modern devices.
  • Audio playback capture: To support captioning or gameplay recording, enable audio playback capture in your app -- it’s a great way to reach more users and make your app more accessible.
  • Better codecs: For media apps, try AV1 for video streaming and HDR10+ for high dynamic range video. For speech and music streaming, you can use Opus encoding, and for musicians, a native MIDI API is available.
  • Better networking APIs: If your app manages IoT devices over Wi-Fi, try the new network connection APIs for functions like configuring, downloading, or printing.

To read about all of the new features and changes, visit the Android 10 developer site.

To get started developing, download the official API 29 SDK and tools into Android Studio 3.5 or higher. Then follow these instructions to configure your environment.

Coming to a device near you!

Android 10 will begin rolling out today to the three generations of Pixel phones -- Pixel 3 (and 3a), Pixel 2, and even the original Pixel! All Pixel devices will get the update over the next week, including those enrolled in this year’s Beta program. If you own a Pixel device, watch for your official over-the-air update coming soon!

As always, the system images for Pixel devices are available here for manual download and flash, and 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 10 source, you'll find it here in the Android Open Source Project repository under the Android 10 branches.

What’s next?

We'll soon be closing the Android Beta issue tracker and Feedback app, but please keep the feedback coming! You can file a new issue against Android 10 in the AOSP issue tracker.

Thanks again to the many developers and early adopters who participated in the Android Beta program this year! You gave us great feedback, and filed thousands of issues that helped us to make the Android 10 platform great for consumers and developers.

We're looking forward to seeing your apps on Android 10!

Committed to a safer Google Play for Families

Posted by Kanika Sachdeva, Product Manager, Google Play

In May, we launched new Families policies to provide additional protections for children and families on Google Play. As part of this policy change, we’re requiring all developers to provide information on their app’s target audience and content via the Google Play Console by September 1st. Thanks to everyone who has completed it already. If you haven’t done so, please fill it out as soon as possible and consult our developer guide and training course for additional information.

Apps that include children in their target audience need to adhere to our new policy requirements including appropriate content, showing suitable ads (learn more), and disclosing personally identifiable information correctly. We’ve found that checking for these requirements takes longer than the normal review process, and can result in review times of up to 7 days (or longer in certain exceptional circumstances). Apps who submit inaccurate responses in the target audience and content section will also be subject to these reviews. You can find more details on Google Play’s app submission process in this Help Center article.

We respect that you are running a business and longer review times can impact how you work. Our goal is to prepare you for this change and minimize disruptions for you. These apps will be subject to extended reviews for every update, and you may need to update your processes to accommodate for additional review time. Suggestions for how to best adapt to this change include submitting your app at least a week before any important launch dates and (unless urgent) avoid resubmitting your app while it is under review.

These changes help make the Play Store safer through deeper and longer reviews, which is a tradeoff we think everyone is willing to make. Thanks for your continued support in building a positive and safe experience for all users on Google Play.

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Expanding bug bounties on Google Play

Posted by Adam Bacchus, Sebastian Porst, and Patrick Mutchler — Android Security & Privacy

We’re constantly looking for ways to further improve the security and privacy of our products, and the ecosystems they support. At Google, we understand the strength of open platforms and ecosystems, and that the best ideas don’t always come from within. It is for this reason that we offer a broad range of vulnerability reward programs, encouraging the community to help us improve security for everyone. Today, we’re expanding on those efforts with some big changes to Google Play Security Reward Program (GPSRP), as well as the launch of the new Developer Data Protection Reward Program (DDPRP).

Google Play Security Reward Program Scope Increases

We are increasing the scope of GPSRP to include all apps in Google Play with 100 million or more installs. These apps are now eligible for rewards, even if the app developers don’t have their own vulnerability disclosure or bug bounty program. In these scenarios, Google helps responsibly disclose identified vulnerabilities to the affected app developer. This opens the door for security researchers to help hundreds of organizations identify and fix vulnerabilities in their apps. If the developers already have their own programs, researchers can collect rewards directly from them on top of the rewards from Google. We encourage app developers to start their own vulnerability disclosure or bug bounty program to work directly with the security researcher community.

Vulnerability data from GPSRP helps Google create automated checks that scan all apps available in Google Play for similar vulnerabilities. Affected app developers are notified through the Play Console as part of the App Security Improvement (ASI) program, which provides information on the vulnerability and how to fix it. Over its lifetime, ASI has helped more than 300,000 developers fix more than 1,000,000 apps on Google Play. In 2018 alone, the program helped over 30,000 developers fix over 75,000 apps. The downstream effect means that those 75,000 vulnerable apps are not distributed to users until the issue is fixed.

To date, GPSRP has paid out over $265,000 in bounties. Recent scope and reward increases have resulted in $75,500 in rewards across July & August alone. With these changes, we anticipate even further engagement from the security research community to bolster the success of the program.

Introducing the Developer Data Protection Reward Program

Today, we are also launching the Developer Data Protection Reward Program. DDPRP is a bounty program, in collaboration with HackerOne, meant to identify and mitigate data abuse issues in Android apps, OAuth projects, and Chrome extensions. It recognizes the contributions of individuals who help report apps that are violating Google Play, Google API, or Google Chrome Web Store Extensions program policies.

The program aims to reward anyone who can provide verifiably and unambiguous evidence of data abuse, in a similar model as Google’s other vulnerability reward programs. In particular, the program aims to identify situations where user data is being used or sold unexpectedly, or repurposed in an illegitimate way without user consent. If data abuse is identified related to an app or Chrome extension, that app or extension will accordingly be removed from Google Play or Google Chrome Web Store. In the case of an app developer abusing access to Gmail restricted scopes, their API access will be removed. While no reward table or maximum reward is listed at this time, depending on impact, a single report could net as large as a $50,000 bounty.

As 2019 continues, we look forward to seeing what researchers find next. Thank you to the entire community for contributing to keeping our platforms and ecosystems safe. Happy bug hunting!

The Google Play store’s visual refresh

Boris Valusek, Design Lead, Google Play

The Google Play Store has over two billion monthly active users coming to find the right app, game, and other digital content. To improve the overall store experience, we’re excited to roll out a complete visual redesign. Aligning with Material design language, we’re introducing several user-facing updates to deliver a cleaner, more premium store that improves app discovery and accessibility for our diverse set of users.

Google Play store's visual refresh

To make browsing faster and easier, we’ve introduced a new navigation bar at the bottom of the Play Store on mobile devices and a new left navigation on tablets and Chrome OS. There are now two distinct destinations for games and apps, which helps us better serve users the right kind of content. Once users find the right app or game, the updated store listing page layout surfaces richer app information at the top of each page as well as a more prominent call-to-action button. This makes it easier for users to see the important details and make a decision to install your app. You’ll also notice our new icon system with a uniform shape, helping content to stand out more over UI. If you haven’t done so already, make sure to update your icon following the new icon specifications as soon as possible.

If you’re looking for best practices to make a compelling store listing page, we have several resources to help. To ensure your page resonates well with Android users, use store listing experiments to test for the best app icon, images, video, and descriptions on Google Play. You can also tailor your marketing messages to specific user groups based on their country, install state or even pre-registration by creating custom store listings. For even more, try our free e-learning resource, Academy for App Success.

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Android Studio 3.5: Project Marble goes into stable

Posted by Jamal Eason, Product Manager, Android

Android Studio logo

Have you ever wished that Android Studio was faster, more performant, and more memory efficient? If so, then download Android Studio 3.5 today. This stable version of Android Studio is a different kind of release where the Android Studio team took a step back from large feature work for eight months and instead focused on product quality to further accelerate your day-to-day app development. We called this initiative Project Marble, and it focused on making the fundamental features and flows of Android Studio & Emulator rock-solid by looking at three core areas: system health, feature polish, and bugs. Working on Project Marble was is in direct response to feedback from you and we continue to welcome any further feedback you have.

To improve system health in Android Studio, we first created a new set of infrastructure and internal dashboards to better detect performance problems. We did this to establish a safety net to catch issues that are typically difficult to catch with regular unit testing. Then, the team addressed a range of issues from fixing over 600 bugs, 50 memory leaks, 20 IDE hangs, and improving XML & Kotlin typing latency. Additionally, for the Android Emulator, we decreased the CPU and memory impact on your development machine. Project Mable was a focused period to work on the IDE and Android Emulator system health but it also uncovered a set of quality areas we will continue to work on going forward.

On top of memory and performance, we spent time polishing and fixing core user facing feature areas. For example, we took a look at the app deployment flow to a device, and completely re-architectured and replaced Instant Run with Apply Changes so that it’s more reliable and trusted. With Apply Changes, we no longer modify an APK during your build but instead, we use runtime instrumentation to redefine classes on the fly. If you want to quickly edit code and see code changes, you should try Android Studio 3.5 today.

Lastly, over the course of Project Marble we fixed bugs which landed in Android Studio in 3.5. We are thankful to those who filed bug reports and engaged with us on social media. We are especially thankful for the over 40 external contributors in the Android community that diligently worked with us in filing and resolving critical quality issues in Android Studio 3.5. Project Marble is not the end of quality work for the Android Studio team, but this latest stable release is a major milestone of our on-going quality investment into the IDE. With the quality work and new infrastructure put in place during Project Marble, we hope that you are even more productive in developing Android apps when you download and use Android Studio 3.5.

There are many quality changes we made to Android Studio 3.5. To see the full list of changes, see the Android Studio 3.5 beta release blog and release notes. But you can dive into some of the highlights of the changes below:

System Health

System health improvements during Project Marble was a combination of memory performance, typing & user interfaces freezes, build speed, CPU usage, and I/O performance. For each of these areas we created new ways to detect issues during development and a better process to analyze your feedback both from opt-in analytics and bugs that you file.

Our system health work has many under the hood improvements but a few notable changes include:

Auto-recommend Memory Settings

With Android Studio 3.5, the IDE will recognize when an app project needs more RAM on a machine with higher RAM capacity and will notify you to increase the memory heap size or you can adjust the settings yourself under Appearance & Behavior → Memory Settings.

Memory Settings

Memory Settings

User Interface Freezes

During the Project Marble development timeframe, we found in our opt-in product analytics that XML code editing was notably slower in the IDE. With this data point, we optimized XML typing, and have measurably better performance in Android Studio 3.5. You can see below that editing data binding expressions in XML is faster due to typing latency improvements.

Code Editing Before

Code Editing Before - Android Studio 3.4

Code Editing After - Android Studio 3.5

Build Speed

For Android Studio 3.5 we made many speed improvements but a significant change is the addition of incremental build support to the top annotation processors including Glide, AndroidX data binding, Dagger, Realm, and Kotlin (KAPT). Incremental support can make a notable impact on build speed. Learn more here.

Disk I/O File Access Speed

For users on Microsoft® Windows®, we found that disk I/O access times were notable higher on average than other platforms. Digging into the data, we found the default configuration of anti-virus scanners did not optimally exclude build output folders. In Android Studio 3.5, we detect this situation and help guide you through the optimal setup.

System Health Notification

System Health Notification - Anti-virus Check

Feature Polish

In addition to improving system health we relooked at a few critical users flows to address bugs and user friction. The areas we looked at ranged from data binding, layout editor, ChromeOS support to project upgrades. One notable area of improvement to highlight is the app deployment flow:

Apply Changes

During the Project Marble time period, we removed Instant Run and re-architectured and implemented from the ground-up a more practical approach in Android Studio 3.5 called Apply Changes. Unlike Instant Run, Apply Changes does not modify your APK which means it is realbile and has a predictable behavior. To support the changes, we re-architected the entire deployment pipeline to improve deployment speed, and also tweaked the run and deployment toolbar buttons for a more streamlined experience.

Apply Changes Buttons

Apply Changes Buttons

App Deployment User Flow

App Deployment User Flow

To recap, Android Studio 3.5 has hundreds of bug fixes and notable changes in these core areas:

System Health

  • Memory Settings
  • Memory Usage Report
  • Reduce Exceptions
  • User Interface Freezes
  • Build Speed
  • IDE Speed
  • Lint Code Analysis
  • I/O File Access
  • Emulator CPU Usage

Feature Polish

  • Apply Changes
  • Gradle Sync
  • Project Upgrades
  • Layout Editor
  • Data Binding
  • App Deployment
  • C++ Improvements
  • Intellij 2019.1 Platform Update
  • Conditional Delivery for Dynamic Feature Support
  • Emulator Foldables & Google Pixel Device Support
  • Chrome OS Support

Check our the Android Studio release notes page for more details and read about deep dives into several areas of Project Marble in the following Medium blog posts & Google I/O talk:

Opt-In & Feedback

The specific areas and the approach we took to optimize Android Studio for Project Marble were all based on your feedback and metrics data. The aggregate metrics you can opt-in to inside of Android Studio allow us to figure out if there are broader problems in the product for all users, and the data also allows the team to prioritize feature work appropriately. There are are a couple pathways to help us build better insights. At a baseline, you can opt-in to metrics, by going to Preferences /Settings → Appearance & Behavior → Data Sharing.

IDE Data Sharing

IDE Data Sharing

Additionally, throughout the year, you might see user sentiment emojis in the bottom corner of the IDE. Those icons are a lightweight way to inform the Android Studio team on how things are going and to give us in-context feedback, and the fastest way to log a bug and send to the team.

IDE User Feedback

IDE User Feedback

Getting Started

Download

Download Android Studio 3.5 from the download page. If you are using a previous release of Android Studio, you can simply update to the latest version of Android Studio.

To use the mentioned Android Emulator features make sure you are running at least Android Emulator v29.1.9 downloaded via the Android Studio SDK Manager.

As mentioned above, we appreciate any feedback on things you like, and issues or features you would like to see. If you find a bug or issue, feel free to file an issue. Follow us -- the Android Studio development team ‐ on Twitter and on Medium.

Improving Accessibility in the Android Ecosystem

Posted by Ian Stoba, Program Manager, Accessibility Engineering

With billions of Android devices in use around the world and millions of apps available on the Play Store, it might seem difficult to drive change across the entire ecosystem, but the Accessibility Developer Infrastructure team is doing just that.

Every time a developer uploads an APK or app bundle to the open or closed tracks, Play tests this upload on various device models running different versions of Android and generates a pre-launch report to inform the developer of issues.

One year ago, the team added accessibility suggestions to the report based on industry best practices and Google’s own experience. These tests check for common issues that can make an app harder to use by people with disabilities. For example, they check that buttons are large enough to be comfortable for people to press, and that text has enough contrast with the background to be easier to read.

Since launching in July 2018, more than 3.8 million apps have been tested and over 171 million suggestions have been made to improve accessibility. Along with each suggestion, the developer gets detailed information about how to implement it. Every developer, from a one-person startup to a large enterprise, can benefit from the accessibility suggestions in the pre-launch report.

We are already seeing the real-world impact of these efforts. This year at Google I/O, the number of developers signing up for in-person accessibility consultations was four times the number from 2018. Googlers staffing these sessions reported that the developers had specific questions that were often based on the suggestions from the pre-launch report. The focused questions allowed the Googlers to give more actionable recommendations. These developers found that improving accessibility isn't just the right thing to do, it also makes good business sense by increasing the potential market for their apps.

Accessibility tests in the pre-launch report are just one way Google is raising awareness about accessibility in the global developer community. We partnered with Udacity to create a free online course about web accessibility, released our Accessibility Scanner for Android on the Play Store, and published iOS Accessibility Scanner on GitHub, allowing iOS developers to easily instrument apps to accessibility tests. Together, these efforts support Google's mission to organize the world's information and make it universally accessible and useful.

Learn more about developing with accessibility in mind by visiting the Android Developer Guidelines and the Google Developer Documentation Style Guide.

Google releases source code for Google I/O 2019 for Android

Posted by Takeshi Hagikura, Developer Programs Engineer

Today we're releasing the source code for the official Google I/O 2019 Android app.

This year's app substantially modified existing functionality and added several new features. In this post, we’ll highlight several notable changes.

Android Q out of the box

  • Gesture navigation

Android Q introduced an option for fully gestural navigation, allowing the user to navigate back and to the home screen using only gestures. To support gesture navigation, app developers need to do two things:

  1. Extend app content to draw edge-to-edge
  2. Handle any conflicting app gestures

The Google I/O 2019 app was one of the first apps to support fully the gestural navigation. For more details, check out this series of blog posts about gesture navigation and the commit in the Google I/O app repository that extended the content to draw edge-to-edge.

Gesture navigation navigating back and to the home screen

  • Dark theme

Another new feature that was introduced with Android Q was the new system Dark theme that applies to both the Android system UI and apps running on Android devices. Dark theme brings many benefits to developers, including being able to reduce power usage and improving visibility for users with low vision and those who are sensitive to bright light.

To support the dark theme, you must set the app’s theme to inherit from a dark theme.

<style name="AppTheme" parent="Theme.AppCompat.DayNight">
OR
<style name="AppTheme" parent="Theme.MaterialComponents.DayNight">


You also need to avoid hard-coded colors or icons. You should use theme attributes (such as ?android:attr/textColorPrimary) or night-qualified resources (such as colors defined both in the res/values/colors.xml and res/values-night/colors.xml) instead. Check out the Google I/O talk about Dark Theme & Gesture Navigation for more details or the series of commits (1, 2, 3) in the Google I/O 2019 app repository for how we achieved implementing the dark theme in a real app.

Schedule UI in dark theme

Improved schedule screen

In 2018, we adopted a tabbed interface for the schedule UI with horizontal swiping, each tab represented a conference day. In 2019, we changed the UI to address some usability and performance problems. For example, the views in the all tabs were rendered at the same time when the schedule UI became visible. That caused a noticeable UI slowdown especially on a low-end device.

The new schedule UI is a single stream, allowing the app to render only visible content and users to easily jump to another conference day by choosing a day at the top of the UI. Check out the series of commits (1, 2) for how we revamped the schedule UI.

This year’s schedule UI jumping to another conference day

Navigation component

We introduced Navigation component to simplify this year’s app into a Single Activity app and observed the following benefits:

  • Being able to see all the transitions at a glance in the navigation editor which simplified launching Session Details and the Map from launch actions
  • Removed boiler plate code for handling up and back navigations
  • Arguments between Fragments were statically typed by using the Safe Args gradle plugin

Check out the getting started guide for how you can start introducing the Navigation component in your app and the series of commits (1, 2, 3, 4) in the Google I/O 2019 app repository for the usage in a real app.

All transitions in the navigation editor

Full Text Search with Room

For this year’s app we added a search feature for users to quickly find sessions, speakers, and codelabs. To accomplish this, we used the Full Text Search feature of the Room Jetpack component. Whenever the conference data is fetched from the server, we update the session, speaker, and codelab data in the Room tables, which have corresponding FTS mapping tables. When a user starts typing in the search box, the search term is used to query the session title and description, speaker names, and codelab title. The search results are shown almost instantly, which allows the search results to be updated with each character typed in the search field. The user can then tap on a search result to navigate to see the details on the session, speaker, or codelab. Check out the series of commits (1, 2, 3, 4) for how we achieved the Full Text Search feature.

Searching for a session and a speaker

Lots of improvements

These were the biggest changes we made to the app, but we improved a lot of little things as well. We added the new Home UI, allowing the app to tell the user time relevant information during the conference and the Codelab UI, which gave users more information about codelabs at I/O and how to participate in them.

Home UI and Codelabs UI

We also introduced Firebase Remote Config to toggle the visibility of each feature by updating the boolean values in the Remote Config without updating the app and removed the hard-coded values that were used for representing start and end time of each event in the Agenda UI.

Go explore the code

If you’re interested go checkout the code and let us know what you think. If you have any questions or issues, please let us know via the issue tracker on GitHub.


Nexon increases day 60 retention and monetization with pre-registration rewards

Posted by Kacey Fahey, Google Play Developer Marketing

Nexon Korea Company has published several games across PC, mobile, and console. With the launch of their mobile game FAITH, a MMORPG released exclusively in Japan, they wanted to promote the game before launch and find a way to capture early consumer demand that would help boost early installs at launch.

What they did

Nexon ran a pre-registration campaign on Google Play with a multi-channel marketing campaign driving players to pre-register and receive an exclusive pre-registration reward. Their campaign used consistent creative assets throughout TV commercials, YouTube influencer campaigns, social media, performance marketing campaigns, and more. Offering a pre-registration reward provided an incentive and benefit for players who pre-registered on Google Play during the month-long campaign leading up to launch.

Banner for mobile game FAITH, a MMORPG released exclusively in Japan

“It was very easy to run, since the steps to activate the campaign were very clear and simple. All we needed to do was prepare the store assets and APK, then set them up in the Google Play Console,” said Hyomin Kim, Head of Platform Partnerships at Nexon Korea Corporation. Their exclusive pre-registration reward of 300 diamonds (in-game currency) was set up as a unique managed product as part of the campaign. At launch, Google Play provides the reward to all players who pre-registered, allowing Nexon to consume and grant the reward to players in-game using the Google Play Billing API. Not only did this create additional value for users, but it allowed Nexon to identify those who pre-registered in-game so they could measure the cohort’s performance after launch. Once the game became available on launch day, everyone who pre-registered on Google Play received a notification to install.

Results

Nexon reported they had historically seen around 50% of Google Play pre-registrations convert to installs. By offering a pre-registration reward for FAITH, they increased their conversion rate by 20%. And not only that, the campaign drove other strong performance metrics with players who pre-registered for FAITH on Google Play having almost 50% higher day 60 retention than those who did not pre-register. This audience has also shown stronger monetization behavior, with over 70% higher ARPDAU than non-pre-registrants.

“Google Play pre-registration is now a ‘must-do’ strategy when Nexon launches games. From our previous experience, Google Play pre-registration is one of the most effective pre-registration platforms amongst all the channels we utilize, especially for organic impressions and installation conversion,” said Kim.

Get started

All app and game developers can run pre-registration campaigns and offer a pre-registration reward. Get started today!