Tag Archives: #Android12

Android 12 Developer Preview 3

Posted by Dave Burke, VP of Engineering

Android 12 logo

Google I/O 2021 is just a few weeks away and we’re looking forward to sharing all of the latest news in Android with you soon! To take us one step closer, today we’re sharing Developer Preview 3, the next milestone release of Android 12, for your testing and feedback.

In Android 12 we’re continuing to focus on making the OS smarter, easier to use, and better performing, with privacy and security at the core. We’re also working to give you new tools for building great experiences for users on phones, laptops, tablets, TVs, or cars. Some things to check out in today’s release include a new app launch experience, new video and camera capabilities to help you get more out of underlying hardware support, and a new permission for exact alarms to help users save battery.

Read on for more highlights and visit the Android 12 developer site for details and downloads for Pixel. If you’re already running a Developer Preview 2 build, watch for an over-the-air (OTA) update coming to you soon! As always, let us know what you think, and thanks for all of the feedback you’ve shared so far.

Better user experience tools

Today’s release includes new tools to help you deliver a polished experience and better performance for users. Here are some of the updates.

Improved app launch experience - In Android 12 we’re making app startup a more consistent and delightful experience. We’ve added a new app launch animation for all apps from the point of launch, a splash screen showing the app icon, and a transition to the app itself. The new experience brings standard design elements to every app launch, but we’ve also made it customizable so apps can maintain their unique branding. For example, you can use new splashscreen APIs and resources to manage the splash screen window’s background color; you can replace the static launcher icon with a custom icon or an animation; you can control the timing to reveal the app; and you can set light mode or dark mode, and manage exit animation.

There’s nothing you need to do to take advantage of the new experience - it’s enabled by default for all apps. We recommend testing your app with the new experience soon, especially if you’re already using a splash screen. To customize the experience, check out the new APIs and let us know what you think. More here.

New call notification template - Incoming and ongoing calls are important to users and they need to be easy to see and manage. In Android 12 we’re improving call notifications to give them more visibility and scannability, and improve their consistency with other notification components. If your app handles calls - such as a dialer app or chat app with video calling - you’ll want to try our new CallStyle template. You can use the template to create notifications for incoming, outgoing, and screened calls. Each type supports multiple actions, including default actions and custom actions that are specific to your app. You can also attach a large avatar image, provide text, and set button color hints. The OS gives CallStyle notifications high visibility, such as bringing them to the top of the notifications shade. More here.

New permission for exact alarms - Alarms are an important way for apps to schedule work. In most cases, apps should use inexact alarms, which have the advantage of being battery-friendly. Android manages these alarms to minimize wakeups and battery impacts, such as through Doze and App Standby. For cases where you need alarms with precise timing - for example alarm clocks and timers - you can use exact alarms instead. These are convenient and reliable, but they can also cause battery drain, especially when overused. So in Android 12, we’re making some changes to give users more control.

Apps targeting Android 12 that want to use exact alarms will now need to request a new permission, SCHEDULE_EXACT_ALARM. It’s a normal permission, so once you’ve declared it in your manifest, you’ll be automatically granted it at first startup. However, we’re also giving users visibility over the apps that have this permission and letting them grant and revoke it from Special App Access Permissions in Settings. If your app requires exact alarms, make sure you handle cases where it no longer has the permission. We’ve added a new API, canScheduleExactAlarms(), to let you check the permission status for your app. In general, we recommend migrating your apps away from uses of exact alarms wherever possible. More here.

Improved web linking - In Android 12 we’re making some changes to help users get to their content faster and more seamlessly. First, we’ve changed the default handling of links that aren’t verified through Android App Links or manually approved for links by the user. Now the OS will directly open them in the default browser, rather than showing a chooser dialog. To make it easier for users to approve your app for links, we’ve added a new Intent that takes them to “Open by default” in Settings. If you want to ensure that only your app can handle links from your domain, you can use App Links. We’ve added new adb commands to help you configure and test your links. More here.

Rich haptic experiences - We’re expanding the tools we offer for creating informative haptic feedback for UI events, immersive and delightful effects for gaming, and attentional haptics for productivity. We’ve added expressive effects like low tick that take advantage of the broader frequency bandwidth of the latest actuators. Game developers can now access multiple, different actuators independently in game controllers to deliver the same effect synchronously or different haptic effects on multiple actuators. For developers, we recommend using the constants and primitives as building blocks for rich haptic effects - constants to enhance UI events and haptic composer to sequence primitives for more complex effects. You can try these APIs to the fullest on Pixel 4 devices today, and we’re continuing to work with our device-maker partners to bring the latest in haptics support to users across the ecosystem.

Video encoding improvements - Android 12 standardizes the set of keys for controlling the range of the video Quantization Parameters (QP), allowing developers to avoid vendor-specific code. The new keys are available in the MediaFormat API and also in the NDK Media library. Video encoders must specify a minimum video quality threshold to ensure that users don't experience extremely low quality when videos are complex.

Camera2 vendor extensions - Many of our device manufacturer partners have built custom camera effects—such as bokeh, HDR, night mode, and others—that they want apps to use to create differentiated experiences on their devices. We’ve already supported these custom effects through a set of vendor extensions in our CameraX library, and now in Android 12 we’re exposing the vendor extensions directly in the platform as well. This helps apps that have complex Camera2 implementations to take advantage of the extensions without having to make significant changes to legacy code. The extension APIs expose exactly the same set of effects as in CameraX, and those are already supported on many different devices, so you can use them right out of the box. More here.

Quad bayer camera sensor support - Many Android devices today ship with ultra high-resolution camera sensors, typically with Quad / Nona Bayer patterns, and these offer great flexibility in terms of image quality and low-light performance. In Android 12, we’re introducing new platform APIs that let third-party apps take full advantage of these versatile sensors. The new APIs support the unique behavior of these sensors and take into account that they might support different stream configurations and combinations when operating in full resolution or ‘maximum resolution’ mode vs ‘default’ mode.

Faster machine learning - In Android 12, we invested in key areas so that developers can make the most of ML accelerators and always get the best possible performance through the Neural Networks API. In terms of performance improvements - we have more than halved inference call overhead by introducing improvements such as padding, sync fences and reusable execution objects. We’ve also made ML accelerator drivers updatable outside of platform releases, through Google Play services. This will make it easier for developers to take advantage of the latest drivers on any compatible device, and make sure that ML performance improvements and bug fixes reach users faster than ever before.

Standardizing GPU compute - We are deprecating the RenderScript APIs in favor of cross-platform GPU compute solutions such as Vulkan and OpenGL. We want you to have confidence that your high-performance workloads will run on GPU hardware, and many devices are already shipping with only CPU support for RenderScript. The existing APIs will continue to work for the time-being, and we've open-sourced a library for RenderScript intrinsics such as blur that uses the highly-optimized intrinsics platform code. Samples and a migration guide for using Vulkan to implement image processing are also available. More here.

Better debugging for native crashes - You've told us that debugging NDK-related crashes can be challenging. We’re making this easier in Android 12 by giving you more actionable diagnostics. In the platform, we use crash dump files called tombstones to debug our native crashes, and they contain the information required to diagnose a variety of issues; this includes unwinding through ART, integrating with fdsan, and recording all the stacks involved in a GWP-ASan, HWASan, or MTE crash. Now we’re giving your app access to its tombstone files through the App Exit Reasons API. When your app uses `ApplicationExitInfo` with `REASON_CRASH_NATIVE`, you can now call `getTraceInputStream()` to get the tombstone data as a protocol buffer.

More-flexible backup configurations - Android’s backup service lets users restore or migrate their data to a new device effortlessly. Apps are central to the experience, enabling users to easily transfer app data and continue where they left off. The backup service supports both cloud backups to Google Drive and device-to-device transfers, and developers can take advantage of these with minimal changes in their apps. For apps targeting Android 12, we’re improving the service to give you more flexibility and control. We’ve updated the XML configuration format so you can now set different rules for cloud backups and device-to-device transfers. With this, for example, you could exclude a large file from cloud backups but include it in device-to-device transfers. You can also set encryption requirements separately for backups or transfers. Last, if you’d like to opt-out of Auto Backup for device-to-device transfers, please use the new configuration format instead of the allowBackup manifest attribute. More here.

You can read more about all of the Android 12 features and behavior changes here.

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.

With Developer Preview 3, we’re moving closer to our first Beta release as we continue to improve stability. Now is the time to try the new features and changes and let us know how these work with your apps. Please visit the feedback page to share your thoughts with us or report issues.

With the first Beta coming soon, it’s time to start your compatibility testing to make sure your app is ready. We recommend releasing a compatible update over the next few weeks. There’s no need to change your app’s targetSdkVersion at this time, although you can use the behavior change toggles to get a preliminary idea of how your app might be affected by opt-in changes in Android 12.

As we reach Platform Stability in August 2021, all of the app-facing system behaviors, SDK/NDK APIs, and non-SDK lists will be finalized. At that point, you can finish up your final compatibility testing and release a fully compatible version of your app, SDK, or library. More on the timeline for developers is here.

App compatibility toggles in Developer Options.

Get started with Android 12

Today’s 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 or using the Android Emulator. If you’ve already installed a preview build to your Pixel device, you’ll automatically get this update and future Beta updates over-the-air. More details on how to get Android 12 are here.

For complete information, visit the Android 12 developer site.

Android 12 Developer Preview 2

Posted by Dave Burke, VP of Engineering

Android 12 logo

Last month we shared the first preview of Android 12, an early look at the next version of Android. Today we’re bringing you the next milestone build in this year’s release, with more new features and changes for you to try with your apps. Our program of early previews is driven by our core philosophy of openness and collaboration with you, our community. Your input helps us make Android a better platform for developers and users, so keep the feedback coming!

In Android 12 we’re making the OS smarter, easier to use, and better performing, with privacy and security at the core. We’re also working to give you new tools for building great experiences for users, whether they’re using phones, laptops, tablets, TVs, or cars. Some things to look for in today’s release include new rounded corners APIs, improved picture-in-picture APIs, better companion device management, easier effects like blur and color filter, app overlay controls, and more.

There’s a lot to check out in Developer Preview 2 - read on for a few highlights and visit the Android 12 developer site for details and downloads for Pixel. For those already running Developer Preview 1 or 1.1, we’re also offering an over-the-air (OTA) update to today’s release.

Let us know what you think, and thank you to everyone who has shared such great feedback so far.

Trust and safety

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 some new features to check out and test with your apps.

App overlay controls - Android’s system alert window gives apps a way to get users’ attention for important actions by showing an overlay on top of the active app. These windows can interrupt the user, though, so we already require apps to request permission before displaying them. Now in Android 12 we’re giving you control over whether these overlays can be shown over your content. After you’ve declared a new permission, your app can call Window#setHideOverlayWindows() to indicate that all TYPE_APPLICATION_OVERLAY windows should be hidden when your app’s window is visible. You might choose to do this when displaying sensitive screens, such as transaction confirmation flows. More here.

Extended security for lockscreen notification actions - Android 12 adds finer-grained privacy and security controls for notifications displayed on the device lockscreen. You can now configure notification actions so that when triggered from the lockscreen, they will always generate an authentication challenge. This extends the notification visibility controls already available through the notification APIs. For example, this enables a messaging app to require authentication before deleting a message or marking it as read. More here.

Access to app digests - For apps that need to validate the integrity of app packages installed on Android devices, we’re introducing a new API that lets you query the platform directly for the checksum of an installed app. You can choose from several digest algorithms such as SHA256, SHA512, Merkle Root, and others. To request a checksum, call PackageManager.requestChecksums() with an app’s package name, the checksum types you need, the installer certs you trust, and a listener to receive the checksums. The platform returns the matching checksums, either precomputed and provided by the installer app (such as Google Play) or computed by the platform. Results are filtered based on package visibility guidelines, so you’ll need to declare the packages of interest in your manifest. This new API provides a simpler, more efficient way to obtain checksums and gives you the stability of a standard, public API that’s optimized for speed and security. For backward compatibility, we’re working on a Jetpack library that provides the same functionality back to API 15 - watch for more details coming soon.

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

Better user experience tools

We’re working to give you more tools to help you deliver a polished experience and better performance for users. Here are some of the updates in today’s release.

rounded corners

Support for Rounded corners - Many modern devices use screens with rounded corners, giving them a clean modern look, but also introducing some extra considerations for app developers. To deliver a great UX on these devices, developers need to account for the rounded corners and adjust any nearby UI elements to prevent them from being truncated.

To help with this, we’re introducing new APIs to let you query for rounded corners and get their details. A RoundedCorner holds the details for a corner, including its radius, centerpoint, and other data. You can call Display.getRoundedCorner() to get the absolute details for each rounded corner. You can also call WindowInsets.getRoundedCorner() to get the corner details relative to your app’s bounds. With these, you can manage the position of UI elements and content as needed. More here.

Picture in Picture (PIP) improvements - for people using gesture nav, we’ve improved how apps transition to picture-in-picture (PIP) mode on swipe up-to-home. If an app enables auto-PIP, the system now directly transitions the app to PIP mode on up-to-home, instead of waiting for the up-to-home animation to complete. This makes the transition smoother and improves perceived performance. We’ve also improved PIP window resizing for non-video content. Apps can now enable seamless resize to let the system resize the PIP Activity when needed. Android 12 also supports stashing the PiP window by dragging it to the left or right edge of the screen. Also, to make PIP windows easier to manipulate, we’ve updated the tap behaviors. Single-tapping now displays controls, and double-tapping toggles the PIP window size. More here.

Keeping companion device apps awake - For apps that manage companion devices like smartwatches and fitness trackers, it can be a challenge to make sure the app is running and connected whenever an associated companion device is nearby. To make this easier, we’re extending the Companion Device Manager with a new CompanionDeviceService API. Apps that manage companion devices can implement this service to let the system wake the app whenever the associated companion device is nearby. The system keeps the service bound whenever the device is nearby, and notifies the service when the device goes in and out of range or is turned off, to let the app clean up state as needed. Apps can also use a new companion device profile when connecting to a watch, which simplifies enrollment by bundling related permissions into a single grant. More here.

Bandwidth estimation improvements - for developers who need to know the typical bandwidth available to each user so you can tailor their experience, we now provide improved bandwidth estimation. We’ve enhanced the existing bandwidth estimation APIs to let you retrieve an estimate of aggregate throughput per carrier or Wi-Fi SSID, network type, and signal level, for all users on the device. The new estimation is likely to be easier and more accurate than most other estimation methods, give it a try and let us know how it works for you.

Easier blurs, color filters and other effects - In Android 12, we’re making it easier to apply common graphics effects to your Views and rendering hierarchies. You can use RenderEffect to apply blurs, color filters, and more to any RenderNode. You can combine these effects as chain effects (which compose an inner and outer effect in order) or blend them. You can also apply effects directly to Views (leveraging the underlying RenderNode) by calling View.setRenderEffect(RenderEffect). 

view.setRenderEffect(RenderEffect.createBlurEffect(radiusX, radiusY, SHADER_TILE_MODE))

Blurring a View with RenderEffect

This allows you to blur the contents of an ImageView without having to get the bitmap data, process the image, create a new Bitmap, and set it back into the ImageView. RenderEffect leverages the existing rendering pipeline to minimize excess calculation.

Give these a try and let use know what you think! More here.

You can also create a frosted glass effect for your window background using a new Window.setBackgroundBlurRadius() API. With this you can set a radius to control the density and scope and the platform applies the blur to the background content within the bounds of your app’s window only. You can also use blurBehindRadius to blur all of the content behind the window to create a depth effect for a floating window.

A dialog window with background blur and blur behind...

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.

With Developer Preview 2, we’re well into the release and continuing to improve overall stability, so now is the time to try the new features and changes and give us your feedback. We’re especially looking for input on our APIs, as well as details on how the platform changes affect your apps. Please visit the feedback page to share your thoughts with us or report issues.

It’s also a good time to start your compatibility testing and identify any work you’ll need to do. We recommend doing the work early, so you can release a compatible update by Android 12 Beta 1. There’s no need to change your app’s targetSdkVersion at this time, but we do recommend using the behavior change toggles to get a preliminary idea of how your app might be affected by opt-in changes in Android 12.

As we reach Platform Stability in August 2021, all of the app-facing system behaviors, SDK/NDK APIs, and non-SDK lists will be finalized. At that point, you can wind up your final compatibility testing and release a fully compatible version of your app, SDK, or library. More on the timeline for developers is here.

App compatibility toggles in Developer Options.

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 or using the Android Emulator. If you’ve already installed a preview build to your Pixel device, you’ll automatically get future updates over-the-air for all later previews and Betas. More details on how to get Android 12 are here.

You can also test your apps on Android TV using today’s release and try the all-new Google TV experience. Learn more here and get started with your ADT-3 developer kit.

For complete information, visit the Android 12 developer site.

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.