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Device capability for billions  |  Android Developers

Reaching new users means supporting an increasing variety of Android platform versions and device specifications.
To improve the user experience, optimize for common RAM configurations, and screen sizes and resolutions.

Support multiple screen sizes

Your app can provide a better user experience for billions of users if it supports screens
of various sizes and resolutions. This section describes a few ways you can do this.

Use density-independent pixels (dp)

  • Defining layout dimensions with pixels doesn't work well because different screens have different pixel densities,
    so the same number of pixels may correspond to different physical sizes on different devices.

  • To overcome this Android supports the density-independent pixel (dp),
    which corresponds to the physical size of a pixel at 160 dots per inch (mdpi density).

  • Defining layouts with dp ensures that the physical size of your user interface is consistent regardless of device.
    Visit the Android guide on
    Supporting Multiple Screens
    for best practices on using density-independent pixels.

Test text and graphics on ldpi and mdpi screen densities

  • Test to ensure that your text and graphics work well on low- and medium-density (ldpi and mdpi) screens
    because these are common densities,
    especially in lower-cost devices.
    Look out for text that may be unclear on lower-density screens, where fine details aren't visible.

  • Devices with lower-density screens tend to have lower hardware specifications.
    To ensure that your app performs well on these devices,
    consider reducing or eliminating heavy graphics processing loads,
    such as animations and transitions.

  • For more information about supporting different densities,
    see the Android training on
    Supporting Different Densities.

Test layouts on small and medium screen sizes

  • Validate that your layouts scale down by testing on smaller screens. As
    screen sizes shrink, be very selective about visible UI elements, because
    there is limited space for them.

  • The Material Design guidelines describe
    metrics and keylines
    to ensure that your layouts can scale across screen densities.

  • For more information about supporting different screen sizes,
    see the Android training on
    Supporting Different Screen Sizes.

Provide backward compatibility

Not all of your users may be using devices powered by the latest, greatest version
of the Android platform. Here are some ways you can improve backward compatibility,
helping make your app available to as many people as possible.

Set your targetSdkVersion and minSdkVersion

  • Apps should build and target the most recent version of Android to ensure
    they offer the most current behavior across a broad range of devices;
    this still provides backward compatibility to older versions.
    Here are the best practices for targeting API levels appropriately:

    • targetSdkVersion
      should be the latest version of Android.
      Targeting the most recent version ensures that your app inherits newer
      runtime behaviors when running newer versions of Android. Be sure to
      test your app on newer Android versions when updating the
      targetSdkVersion as it can affect app behavior.

    • minSdkVersion
      Sets the minimum supported Android version.
      Setting minSdkVersion also results in the Android build
      tools reporting incorrect use of new APIs that might not be available in
      older versions of the platform. By doing so, you are protected
      from inadvertently breaking backward compatibility.

  • Consult the
    Android dashboards
    , the Google Play Developer
    for your app, and industry research in your target markets to
    gauge which versions of Android to target, based on your target users.

Use the Android Support libraries

  • Ensure your app provides a consistent experience across OS versions by using the
    Android Support Library.
    This library provides backward-compatible versions of Android framework APIs
    as well as features that are only available through the library APIs
    such as AppCompatActivity and the Material Design Support Library.

  • Some of the highlights include:

  • For more information about the available support libraries, see the
    Support Libraries Features
    section of the Android Developer site.

Use Google Play services

  • Google Play services brings the best of Google APIs independent of
    Android platform version. Consider using features from Google Play services
    to offer the most streamlined Google experience on Android devices.

  • Google Play services also include useful APIs such as
    , which provides much of Android 5.0's
    JobScheduler API for older versions of Android.

  • Updates to Google Play services are distributed automatically by the
    Google Play Store, and new versions of the client library are delivered
    through the Android SDK Manager.

Use memory efficiently

Memory is an unsung hero of the user experience. Good memory management can make your
app more stable and more performant; in some cases, its effective use may be the only thing making
your app usable at all. Here are some ways you can help your app use memory wisely.

Reduce memory footprint on low-cost devices

  • Adjust your memory footprint dynamically to ensure compatibility
    across devices with different RAM configurations.

  • Methods such as isLowRamDevice() and
    getMemoryClass() help determine memory
    constraints at runtime. Based on this information, you can scale down your
    memory use. As an example, you can use lower resolution images on low memory

  • For more information about managing your app's memory, see the Android
    training on Managing
    Your App's Memory

Avoid long-running processes

  • Long-running processes stay resident in memory and can slow
    down the device. In most situations, your app should wake up for a given
    event, process data, and shut down. You should use Firebase Cloud Messaging
    to avoid long running background
    services and reduce memory pressure on the user's device.

Benchmark memory use

Android Studio provides memory benchmarking and profiling tools, enabling
you to measure memory use at run time. Benchmarking your app's memory
footprint enables you to monitor memory use over multiple versions of
the app. This can help catch unintentional memory footprint growth. Use the
Memory Profiler tool to do the following:

  • Find out whether undesirable garbage collection (GC)
    event patterns might be causing performance problems.

  • Identify object types that get or stay allocated unexpectedly or

  • Identify where in your code the problem might be.

For more information about benchmarking memory use, see

View the Heap and Allocations with Memory Profiler

Optimize for devices running Android (Go edition)

Android (Go edition) is an optimized experience
for entry-level devices with ≤1GB RAM,
starting with Android Oreo (Go edition).
To ensure your app runs great on Android (Go edition) devices,
you should should take into account the following guidelines:

  • targetSdkVersion
    should be the latest version of Android.
    Android (Go edition) devices only run Android Oreo (API 27 or higher).

  • The app should run smoothly on devices with ≤1GB RAM.
    Keep in mind the memory optimizations listed in
    Use memory efficiently above
    and use Android vitals
    to identify and fix bad behaviors like slow rendering and frozen frames.

  • Picture in picture (PIP) might be disabled
    on devices. Before your app uses PIP, check to be sure it is available by
    calling hasSystemFeature(PackageManager.FEATURE_PICTURE_IN_PICTURE).

  • The on-device app size should be smaller than 40MB.

  • The Proportional Set Size (PSS) of the app's RAM usage
    should not exceed 90MB. For games, the PSS of the game's RAM usage should not exceed 150MB. For
    more information about PSS, see the Investigating
    Your RAM Usage

  • The startup time of the app should be minimal and under 5 seconds.


    (which allows apps to draw a window on top of other apps) might be disabled on
    Android Go devices that have low RAM. Before drawing over other apps, check whether your app
    has this authorization by calling

    If your app cannot get the permission, gracefully degrade your app so that the user can
    continue using your app, possibly by disabling the feature that requires the SYSTEM_ALERT_WINDOW

We recommend that most developers optimize their existing app,
which will be available on all Android (Go edition) devices,
because making your app run faster and lighter will benefit your whole audience.
You can use the
Multiple APK feature
on the Play Console to distribute a specific APK
for Android (Go edition) devices
but you should only do so without compromising the experience
(e.g. you should avoid removing features).
The APK targeting Android (Go edition) devices needs to declare
<uses-feature android:name="android.hardware.ram.low" android:required="true">,
target at least API Level 26,
and have a higher version code than the non-Go edition APK.

Additional resources

To learn more about supporting a variety of devices, view the following

Blog posts

Core app quality  |  Android Developers

Last updated: May 17, 2021

A useful way to evaluate app excellence is to walk
through the workflows in your app and evaluate the smoothness and safety of the
app experience.

This checklist defines a set of core quality criteria and associated tests to help you assess the
quality of your app. Some of these criteria might be easy to miss, and the tests help you remember
to include them in your test plans.

The checklist highlights the minimum quality that all apps should meet. Your testing will likely
go well beyond what's described here.

Each item in the quality checklist has a unique ID which you might find helpful to use when you
communicate with your team. You can also view the previous
version of these guidelines

Visual experience

Your app should provide standard Android visual design
and interaction patterns where appropriate, for a consistent and intuitive
user experience.

Area ID Tests Description
Navigation VX-N1 CR-3 The app supports standard Back button navigation and does not make use of any custom, on-screen "Back button" prompts.
VX-N2 CR-3 The app supports gesture navigation for going back / going to the home screen.
VX-N3 CR-1

The app correctly preserves and restores user or app state.

The app preserves user or app state when leaving the foreground and prevents accidental data loss due to back-navigation and other state changes.

When returning to the foreground, the app should restore the preserved state and any significant stateful transaction that was pending. Examples include: changes to editable fields, game progress, menus, videos, and other sections of the app or game.

  1. When the app is resumed from the Recents app switcher, the app returns the user to the exact state in which it was last used.
  2. When the app is resumed after the device wakes from the sleep (locked) state, the app returns the user to the exact state in which it was last used.
  3. When the app is relaunched from Home or All Apps, it should do one of the following, depending on how much time has passed since it was last used:

    • If the app was last used a short time ago (minutes), restore the app state as close as possible to its previous state.
    • If more time has passed since the app was last used, try to restore the app as close as possible to its previous state;
      or start it from its home screen or some other default state.

Notifications VX-S1 CR-9

Notifications follow Material Design guidelines. In particular:

  1. Notifications are not used for cross-promotion or advertising another product, as this is strictly prohibited by the Play Store.

  2. Notification channels are defined according to best practices, rather than serving all notifications from one channel.

  3. Selecting the correct notification priority.

  4. Multiple notifications are stacked into a single notification group, where possible.

  5. Set timeouts for notifications where appropriate.

  6. Notifications are persistent only if related to ongoing events, such as music playback or a phone call. For more information, see the
    Functionality section.

VX-S2 CR-9

For messaging apps, social apps and conversations:

  1. Use the MessagingStyle notifications for conversations.

  2. Support the direct reply action.

  3. Support conversation shortcuts, and implement best practices for getting the best direct share ranking.

  4. Support bubbles.

UI and Graphics VX-U1 CR-5 The app supports both landscape and portrait orientations (if possible) and folding /

Orientations expose largely the same features and actions and preserve functional parity.
Minor changes in content or views are acceptable.

VX-U2 CR-5 The app uses the whole screen in both orientations and does not letterbox to account for
orientation changes, including folding and unfolding.

Minor letterboxing to compensate for small variations in screen geometry is acceptable.

VX-U3 CR-5 The app correctly handles rapid transitions between display orientations and device folding
/ unfolding without rendering problems or losing state.
Visual quality VX-V1 CR-all

The app displays graphics, text, images, and other UI elements without noticeable distortion, blurring, or pixelation.

  1. The app should use vector drawables where possible.
  2. The app provides high-quality graphics for all targeted screen sizes and form factors.
  3. No aliasing at the edges of menus, buttons, and other UI elements is visible.

VX-V2 CR-all

The app displays text and text blocks in an acceptable manner for each of the app’s supported languages.

  1. Composition is acceptable in all supported form factors.
  2. No cut-off letters or words are visible.
  3. No improper word wraps within buttons or icons are visible.
  4. There is sufficient spacing between text and surrounding elements.

VX-V3 CR-all The app’s content, and all web contents referred to by the app, support dark theme.
Accessibility VX-A1 CR-all

Touch targets should be at least 48dp in size.
Learn more.

VX-A2 CR-all

The app’s text and foreground content should maintain a high enough color contrast ratio
with its background:

  • 3.0:1 for large text / graphics

  • 4.5:1 for small text (text smaller than 18pt, or if the text is bold and smaller than 14pt)

Learn more about color and contrast.

VX-A3 CR-all Describe each UI element,
except for TextView, using contentDescription.


Your app should implement the expected functional behavior.

Area ID Tests Description
Audio FN-A1 CR-1
Audio resumes when the app returns to the foreground, or indicates to the user that playback is in a paused state.
FN-A2 CR-1
If audio playback is a core feature, the app should support background playback.
FN-A3 CR-0

When the user initiates audio playback, the app should do one of the following within one second:

  1. Start playing the audio.
  2. Provide a visual indicator that the audio data is being prepared.

FN-A4 CR-0 The app should request audio focus when audio starts playing and abandon audio focus when playback stops.
FN-A5 CR-0 The app should handle other apps’ requests for audio focus. For example, an app might reduce playback volume when another app plays speech.
Media FN-M1 CR-0
If the app plays audio in the background, it must create a Notification styled with MediaStyle.
FN-M2 CR-0 If the app plays video, it should support picture-in-picture playback.
FN-M3 CR-0 If the app encodes video, it should do so using the HEVC video compression standard.
Sharing FN-S1 CR-0 The app should use the Android Sharesheet when sharing content.
It can suggest targets that are unavailable to custom solutions.
Background Service FN-B1 CR-6 The app avoids running unnecessarily long services in the background. To ensure the smooth running of the user’s device, the system applies various restrictions on background services. These are not considered good uses of background services:

  • Maintaining a network connection for notifications
  • Maintaining a Bluetooth connection
  • Keeping the GPS powered-on

Learn how to choose the right solution for your work.

Performance and stability

Your app should provide the performance, stability, compatibility, and
responsiveness expected by users.

Area ID Tests Description
PS-S1 CR-all
The app does not crash or
block the UI thread causing ANR (Android Not
Responding”) errors. Utilize
Play’s pre-launch report
to identify potential stability issues. After deployment, pay
attention to the Android Vitals page in the Google
Play developer console.
Performance PS-P1 CR-all
The app loads quickly or provides onscreen feedback to the user (a progress indicator or similar cue) if the app takes longer than two seconds to load.
PS-P2 CR-all
Apps should render frames every 16ms to achieve 60 frames per second. Developers can use the Profile HWUI rendering option in testing. If there are issues, tools are available to help diagnose slow rendering.
PS-P3 PM-1 With StrictMode enabled (see StrictMode Testing, below), no red flashes (performance warnings from StrictMode) are visible when testing the app. Any red flashes indicate bad behaviors regarding storage, network access, or memory leaks.
SDK PS-T1 CR-0 The app runs on the latest public version of the Android platform without crashing or severely impacting core functionality.
PS-T2 SP-1 The app targets the latest Android SDK needed to align with Google Play requirements by setting the targetSdk value.
PS-T3 SP-1 The app is built with the latest Android SDK by setting the compileSdk value.
PS-T4 SP-2
Any Google or third-party SDKs used are up-to-date. Any improvements to these SDKs, such as stability, compatibility, or security, should be available to users in a timely manner.

For Google SDKs, consider using SDKs powered by Google Play services, when available. These SDKs are backward compatible, receive automatic updates, reduce your app package size, and make efficient use of on-device resources.

The developer is accountable for the entire app’s codebase, inclusive of any third-party SDKs used.

PS-T5 SP-3 The app does not use non-SDK interfaces.
PS-T6 SP-2 No debug libraries are included in the production app. This can cause performance as well as security issues.
Battery PS-B1 BA-1 The app properly supports the power management features that were introduced in Android 6.0 (Doze and App Standby). In the case where core functionality is disrupted by power management, only qualified apps may request an exemption. See Support for other use cases in Doze and App Standby.

During development, developers can test app standby and doze behavior using these ADB commands.

In terms of battery usage, developers can use the Android Studio energy profiler or the Battery Historian tool, combined with planned background work, to diagnose unexpected battery use.

Privacy & security

Your app should handle user data and personal information safely,
with the appropriate level of permission.

In addition to this checklist, applications published on the Google Play
Store must also follow the User Data
to protect users' privacy.

Area ID Tests Description
SC-P1 SC-4 The app requests only the absolute minimum number of permissions that it needs to support its use case at hand. For some permissions such as location, use coarse location in place of fine location if possible.

The app requests permission to access sensitive data (such as
SMS, Call Log, or
or services that cost money (such as Dialer or SMS) only when directly related to the core
use cases of the apps. Implications related to these permissions should be prominently disclosed to the user.

Depending on how you are using the permissions, there might be an
alternative way
to fulfill your app's use case without relying on access to sensitive information. For example, instead of
requesting permissions related to a user’s contacts, it may be more appropriate to request access
by using an implicit intent.

SC-P3 CR-0 The app requests runtime permissions in context, when the functionality is requested, rather than upfront during app startup.
SC-P4 CR-0

The app clearly conveys why certain permissions are needed or follow the recommended flow to
explain why it needs a permission.

SC-P5 CR-0 The app should gracefully degrade when
users deny or revoke a permission. The app should not prevent the user from accessing the app altogether.
Data & Files SC-DF1 SC-1 All sensitive data is stored in the app's internal storage.
SC-DF2 SC-10 No personal or sensitive user data is logged to the system log or an app-specific log.
SC-DF3 The app does not use any non-resettable hardware IDs, such as the IMEI, for identification purposes.
Identity SC-ID1 CR-0 The app provides hints to autofill account credentials and other sensitive information, such as credit card info, physical address, and phone number.
SC-ID2 CR-0 Integrate One Tap for Android for a seamless sign in experience.
SC-ID3 CR-0 The app supports biometric authentication to protect financial transactions or sensitive information, such as important user documents.
App Components SC-AC1 SC-5

The app sets the android:exported attribute explicitly for all activities, services, broadcast receivers, and especially content providers.

Only application components that share data with other apps, or components that should be invoked by other apps, are exported.


All intents and broadcasts follow best practices:

  1. Use explicit intents if the destination application is well defined.
  2. Use Intents to defer permissions to a different app that already has the permission.
  3. Share data securely across apps.
  4. Intents that contain a payload are verified before use.
  5. If you need to pass an Intent to another app, so that the receiving app can invoke and expect a callback in the calling app, do not include a nested intent in the extras. Use a PendingIntent.
  6. When setting up your PendingIntents, explicitly set the immutable flag, where applicable.

SC-AC3 SC-3 All components that share content between your apps use android:protectionLevel="signature" for custom permissions. This includes activities, services, broadcast receivers, and especially content providers.

Apps should not rely on accessing a list of installed packages. The access has been restricted beginning in Android 11.

SC-N1 SC-9 All network traffic is sent over SSL.
SC-N2 SC-6 The application declares a network security configuration.
SC-N3 If the application uses Google Play services, the security provider is initialized at application startup.
SC-W1 SC-6 Do not use setAllowUniversalAccessFromFileURLs() for accessing local content. Instead, use WebViewAssetLoader.
SC-W2 SC-7 WebViews should not use addJavaScriptInterface() with untrusted content.

On Android 6.0 and above, use HTML message channels instead.

Execution SC-E1 The app does not dynamically load code from outside the app's APK. Developers should use Android App Bundles, which includes Play Feature Delivery and Play Asset Delivery.

As of August 2021, the use of Android App Bundles is mandatory for all new apps in the Google
Play Store.

Cryptography SC-C1 The app uses strong, platform-provided cryptographic algorithms and a random number generator. Also, the app does not implement custom algorithms.

Google Play

Be sure that your apps can be published on Google Play.

Area ID Tests Description
Policies GP-P1 GP-all The app strictly adheres to the terms of the Google Play Developer Content Policy and does not offer inappropriate content, does not use the intellectual property or brand of others, and so on.
GP-P2 GP-1 The app maturity level is set appropriately, based on the Content Rating Guidelines.
App Details Page GP-D1 GP-1

The app’s feature graphic follows the guidelines outlined in this
support article. Make sure that:

  1. The app listing includes a high-quality feature graphic.
  2. The feature graphic does not contain device images, screenshots, or small text that will be illegible when scaled down and displayed on the smallest screen size that your app is targeting.
  3. The feature graphic does not resemble an advertisement.

GP-D2 GP-1 The app’s screenshots and videos do not show or reference non-Android devices.
GP-D3 GP-1 The app’s screenshots or videos do not represent the content and experience of your app in a misleading way.
User Support GP-X1 GP-1 Common user-reported bugs in the Reviews tab of the Google Play page are addressed if they are reproducible and occur on many different devices. If a bug occurs on only a few devices, you should still address it if those devices are particularly popular or new.

Setting up a test environment

For the purpose of setting up a test environment for this checklist, we recommend the following:

  • Focused on emulator testing - Android Emulator is a great way to test your app under different Android versions and screen resolutions. You should set up emulated devices (AVDs) to represent the most common form factors and hardware/software combinations for your target user base. In addition to testing for phones, we also recommend you test other form factors using the following emulators at a minimum:

    • Foldables - 7.6” Fold-in with outer display (this is listed under phones in the AVD Manager).

    • Tablet - Pixel C 9.94” (2,560px x 1,800px).

    • For mobile app notification testing, pair a mobile device / emulator with Wear OS emulator - Wear OS Round 1.84”.

  • Hardware devices - Your test environment should include a small number of actual hardware devices that represent the key form factors and hardware/software combinations that are currently available to consumers. It's not necessary to test on every device that's on the market — rather, you should focus on a small number of representative devices, even using one or two devices per form factor.

  • Device test labs - You can also use third party services, such as Firebase Test Lab, to test your app on a wider variety of devices.

  • Test with the latest Android version - In addition to testing representative Android versions for your target user base, you should always test against the latest version of Android (currently Android 11). This ensures that the latest behavior changes do not negatively impact your user’s experience.

For more comprehensive guidance on testing including unit testing, integration testing and UI testing, check out the Android testing fundamentals.

Test procedures

These test procedures help you discover various types of quality issues in
your app. You can combine the tests or integrate groups of tests together in
your own test plans. See the sections above for references that associate
criteria with these test procedures.

Type Test Description
Core Suite CR-0

Navigate to all parts of the app — all screens, dialogs, settings, and all user flows.

  1. If the application allows for editing or content creation, game play, or media playback, make sure to test those flows.

  2. While testing the app, introduce interruptions from other apps, such as receiving a notification or a phone call; and apply transient changes to device attributes, such as network connectivity, battery function, GPS availability, and system load.

  3. Enter and test all in-app purchase flows

CR-1 From each app screen, press the device's Home key or swipe up in gesture navigation, then re-launch the app from the All Apps screen.
CR-2 From each app screen, switch to another running app, and then return to the app under test using the Recents app switcher.
CR-3 From each app screen (and dialogs), press the Back button or use the back swipe gesture.
CR-5 From each app screen, rotate the device between landscape and portrait orientation and folding / unfolding at least three times.
CR-6 Switch to another app to send the test app into the background. Go to Settings and check whether the test app has any services running while in the background. In Android 4.0 and higher, go to the Apps screen and find the app in the "Running" tab.
CR-7 Press the power button to put the device to sleep, then press the power button again to wake the screen.
CR-8 Set up a screen lock on the device. Press the power button to put the device to sleep (which locks the device). Then, press the power button again to wake the screen and unlock the device.
CR-9 Trigger and observe in the notifications drawer all types of notifications that the app can display. Expand notifications where applicable (Android 4.1 and higher), and tap on all available actions.
CR-10 Review Support for other use cases in Doze and App Standby.
Install on SD Card SD-1 Repeat Core Suite with the app installed to a device’s SD card (if the app supports this installation method).

To move the app to SD card, you can use Settings > App Info > Move to SD Card.

Performance and Stability SP-1 Review the Android manifest file and build configuration to ensure that the application is built against the latest available SDK (targetSdk and compileSdk).
SP-2 Review the build.gradle file for any outdated dependencies.
SP-3 Use the Android Studio lint tool to detect non-SDK interface usage. Other alternative testing methods also exist.
Performance Monitoring PM-1 Repeat Core Suite with StrictMode profiling enabled.

Pay close attention to garbage collection and its impact on the user experience.

BA-1 Repeat Core Suite across Doze and App Standby cycles.

Pay close attention to alarms, timers, notifications, syncs, and so on. See Testing with Doze and App Standby for requirements and guidelines.

Security SC-1 Review all data stored in external storage.
SC-2 Review how the data that’s loaded from external storage is handled and processed.
SC-3 Review all content providers defined in the Android manifest file. Make sure each provider has an appropriate protectionLevel.
SC-4 Review all permissions that your app requires, in the manifest file, at runtime, and in the app settings screen (Settings > App Info) on the device.
SC-5 Review all application components defined in the Android manifest file for the appropriate export state. The exported property must be set explicitly for all components.
SC-6 Review the app's Network Security configuration, ensuring that no lint checks on the configuration fail.
SC-7 For each WebView, navigate to a page that requires JavaScript.
SC-8 In each WebView, attempt to navigate to sites and content that aren’t loaded directly by your app.
SC-9 Declare a Network Security Configuration that disables cleartext traffic, then test the app.
SC-10 Run the application and exercise all core functionality, while observing the device log. No private user information should be logged.
Google Play GP-1 Sign into the Google Play Developer Console to review your developer profile, app description, screenshots, feature graphic, content rating and user feedback.
GP-2 Download your feature graphic and screenshots, and scale them down to match the display sizes on the devices and form factors that you are targeting.
GP-3 Review all graphical assets, media, text, code libraries, and other content that’s packaged in the app or expansion file download.

Testing with StrictMode

For performance testing, we recommend enabling StrictMode in your
app and using it to catch operations that could affect performance, network accesses, file
reads/writes, and so on. Look for potentially problematic operations both on the main thread and on
other threads.

You can set up a per-thread monitoring policy using
and enable all supported monitoring in the
ThreadPolicy using

Make sure to enable visual notification of policy violations for the
ThreadPolicy using

Read article
Reduced data cost for billions  |  Android Developers

Data plans in some countries can cost upwards of 10% of a typical user's monthly income. This
means that minimizing your app's download size and letting the user control how your app uses
data can have a large, tangible benefit to many users. Minimizing download size also helps
conserve space in internal storage, which is a scarce resource in some devices.

Here you can find some strategies to help optimize the amount of data your app uses, both over
the network and in internal storage.

Reduce app size

Reducing app size is one of the fundamental ways you can help your user consume less data, in
terms of both network data and internal storage. This section describes several approaches to
reducing app size.

Reduce APK graphical asset size

  • Graphical assets are often the largest contributor to the size of the
    APK. Optimizing these can result in smaller downloads and thus faster
    installation times for users.

  • For graphical assets such as icons, use the Scalable Vector Graphics (SVG)
    format. SVG images are tiny in size compared to bitmap graphics and can be rendered at
    runtime to any resolution. The Android Support Library
    provides a backward-compatible implementation for vector resources to Android 2.1 (API level 7).
    Get started with vectors with
    this Medium post

  • For non-vector images, such as photos, use WebP to reduce
    image load times and save network bandwidth. WebP is proven to result in
    smaller file sizes than its PNG and JPG counterparts, with at least the
    same image quality. Even at lossy settings, WebP can produce a nearly
    identical image to the original. Android has included lossy WebP support since Android 4.0 (API
    level 14: Ice Cream Sandwich) and support for lossless, transparent WebP
    since Android 4.2 (API level 17: Jelly Bean).

  • If you have many large images across multiple densities, consider
    using Multiple
    APK support
    to split your APK by density. This results in builds
    targeted for specific densities, meaning users with low-density devices
    won’t have to incur the penalty of downloading unused high-density assets.

  • For more information about reducing APK size, see
    Reduce APK Size and
    Shrink Your Code and Resources. In addition, you can
    find a detailed guide on reducing APK size in this
    series of Medium posts

Reduce code size

  • Every library in your Android project is adding potentially unused code to the APK. Be
    particularly careful about using external libraries because not all libraries are
    designed for use in mobile apps. Ensure that the libraries your app is
    using are optimized for mobile use.

  • Consider optimizing your compiled code using a tool such as ProGuard. ProGuard identifies
    code that isn’t being used and removes it from your APK. Also
    enable resource shrinking
    at build time by setting
    minifyEnabled=true, shrinkResources=true in
    build.gradle—this automatically removes unused resources from
    your APK.

  • When using Google Play services, you should
    selectively include
    only the necessary APIs into your APK.

  • For more information on reducing code size in your APK, see the Android
    training on how to Avoid
    dependency injection frameworks

Allow app to be moved to external (SD) storage

  • Low-cost devices often come with little on-device storage. Users can
    extend this with SD cards; however, apps need to explicitly declare that
    they support being installed to external storage before users can move them.

  • Allow your app to be installed to external storage using the
    flag in your AndroidManifest.xml. For more
    information on enabling your app to be moved to external storage, see the
    Android guide on App Install

Reduce post-install app disk use

  • Keeping your app’s disk use low means that users are less likely to
    uninstall your app when the device is low on free space. It’s important
    to apply bounds around your caches—this prevents your app’s
    disk use from growing indefinitely. Be sure you put your cached data in
    getCacheDir()—the system can delete files
    placed here as needed, so they won’t show up as storage committed to the

Offer configurable network use

The Android platform includes a number of ways you can give the user control
over your app's network use, optimizing it for their own needs. For example,
on first use, your app can walk the user through a variety of network-related settings.
You can also provide a network preferences screen from outside the app.

Provide onboarding experiences for users' network

  • Apps that allow users to reduce data use are well received, even if
    they have heavy data requirements. If your app uses a considerable amount
    of bandwidth (for example, video streaming apps), you can provide an
    onboarding experience for users to configure network use. For example,
    you could allow the user to force lower-bitrate video streams on cellular

  • Additional settings for users to control data syncing, prefetching, and
    network use behavior (for example, prefetch all starred news categories on
    Wi-Fi only), also help users tailor your app’s behavior to their needs.

  • For more information on managing network use, see the Android training
    on Managing
    Network Usage

Provide a network preferences

  • You can navigate to the app’s network settings from outside the app by
    means of a network preferences screen. You can invoke this screen from
    either the system settings screen or the system data usage screen.

  • To provide a network preferences screen that users can access from within
    your app as well as from the system settings, in your app include an
    activity that supports the

  • For further information on adding a network preferences screen, see the
    Android training on
    Implementing a Preferences Activity

Additional resources

To learn more about this topic, view the following additional resources:

Blog posts

Read article
TV app quality  |  Android Developers

Users have different expectations when watching TV, compared to using a phone or tablet.
A typical TV user sits about 10 feet away from the screen, so small details are less noticeable
and small text is hard to read. Since users sit away from a TV, they must use a remote
control device to navigate and make selections rather than touching elements on the screen. These
differences significantly affect the requirements for what makes a good TV user experience.

The first step toward creating a great experience for TV users is to review and follow the
Android TV design guidelines, which provides
instructions on how to build the best user experience for TV apps. You should also review the
Building TV Apps training, to understand the
fundamental implementation requirements for a TV app.

Important: To ensure a great user experience, apps for TV devices must meet
specific requirements for usability. Only apps that meet the following quality criteria will
qualify as an Android TV app on Google Play.

Note: For information about how to publish your TV apps in Google
Play, see
Distributing to Android TV.

Visual design and user interaction

These criteria ensure that your app follows critical design and interaction patterns
to ensure a consistent, intuitive, and enjoyable user experience on TV devices.






The app displays a launcher icon in the Android TV Launcher after installation.
(Learn how)


The app displays a 320 x 180px full-size banner as its launcher icon in the Android TV Launcher.
(Learn how)


The app launch banner contains the name of the app.
(Learn how)


If the app is a game, it appears in the Games row in the Android TV Launcher.

(Learn how)


The app runs successfully when the user selects the application banner from the home screen.
(Learn how)



All app interfaces are presented in landscape orientation.
(Learn how)


The app displays core text at 16sp or higher in size.
(Learn how)


The app displays all text at 12sp or higher in size.
(Learn how)


The app does not display any text or functionality that is partially cut off by the
edges of the screen.
(Learn how)


The app does not partially obscure other apps. The app fills the entire screen and has a
non-transparent background.


The app functionality is navigable using 5-way D-pad controls, unless the app
requires a gamepad controller as specified in TV-GP.
(Learn how)


If the app requires a game controller, as specified in TV-GP, all
functionality is navigable using standard Android game controller keys.
(Learn how)


The app does not depend on a remote controller having a Menu button to access user interface
(Learn how)


Back button presses lead back to the Android TV home screen.
(Learn how)


For apps with a live TV feed integrated on the Live tab, the app meets frictionless playback and direct-back requirements.
(Learn how)


In-app search results are navigable using D-pad controls, unless the app
requires a gamepad controller, as specified in TV-GP.
(Learn how)


An in-app search query should show up in the search box, similar to the user interface provided
by SearchFragment, and results should be relevant to
that query.
(Learn how)


These criteria ensure that your app is configured correctly and provides the expected
functional behavior.






The app manifest sets an intent type of ACTION_MAIN with category
(Learn how)


The app manifest sets the hardware feature android.hardware.touchscreen to not required.

Game Controllers


If the app uses a game controller as its primary input method, it declares the appropriate
requirement with the <uses-feature> manifest tag.
(Learn how)


If the app provides visual instructions for using game controllers, the instructions should
be free of branding and show a compatible button layout.
(Learn how)



The app allows interaction with advertising using D-pad controls.
(Learn how)


For advertising that uses fullscreen, non-video ads, the app allows the user to
immediately dismiss the ad with D-pad controls.


For advertising that uses clickable, non-fullscreen, non-video ads, the app does not allow
ads to link to a web URL.


For advertising that uses clickable, non-fullscreen, non-video ads, the app does not allow
ads to link to another app that is not available on TV devices.

Web Content


For web content, the app uses WebView components and does not attempt
to launch a web browser app.

Media Playback


If the app continues to play sound or video after the user has returned to the home screen or
switched to another app, the app provides a Now Playing card on the home screen
recommendation row so users can return to the app to control playback.
(Learn how)


If the app provides a Now Playing card, selecting this card takes the user to
a screen that allows playback to be paused.
(Learn how)


If the app plays video or music content, the app toggles between play and pause of media
playback when a play or pause key event is sent during playback.


While a video or audio is playing, pressing the D-pad center button should immediately pause
the media that is playing. When paused, D-pad center button should resume playing. D-pad left
and right buttons should fast forward or rewind the current track.
(Learn how)


When adding items to the Watch Next channel, developers should follow the Watch Next
(Learn how)

Ambient Mode


When there is user-initiated active video playback, the app must prevent the device from
going into Ambient Mode. (Learn How)


When there is no user-initiated active video playback or animation, the app must not
prevent the device from going into Ambient mode.


For audio-only playback, the app must not prevent the device from going to Ambient Mode.
Exception: The app implements an experience of non-static imagery (e.g. music videos, images)
while music is playing.

Privacy & Security


From May 2023, TV apps must comply with App Bundle requirements as outlined in
SC-E1 in the core app

Frequently asked questions

After I submit my app, how will find out if my app does not meet all the requirements for
TV devices?

If your app does not meet the usability requirements described on this page, the Play Store team
will contact you through the email address specified in the Google Play Console account associated with
the app.

Caution: Make sure your app includes the required manifest entries for TV devices,
otherwise your app will not be considered a TV app and will not be reviewed for TV usability

My app targets more than just TV devices. If my app does not meet the TV device
requirements, will my new or updated app still appear on Google Play for other devices?

Yes. The requirements described above only excludes distribution to Google Play on TV
devices. Distribution to other device types, such as phones and tablets, is not affected.

If my app meets the publishing requirements, when will it be available in the Google
Play Store on TV devices?

Apps that meet the requirements for TV will appear on the Play Store on TV devices immediately.

Read article
Battery consumption for billions  |  Android Developers

Access to reliable power supplies varies, and outages can disrupt planned
charges. Defend your users' batteries against unnecessary drain by benchmarking
your battery use, avoiding wakelocks, scheduling tasks, and monitoring sensor

Reduce battery consumption

There are several steps you can take to help make sure that your app
is only consuming battery power when it needs to, and that it's not
consuming more power than necessary.

  • Your app should minimize its activity when in the background and when the
    device is running on battery power.

  • Sensors, such as GPS sensors, can drain battery significantly. Avoid issues by using the
    API to manage the
    underlying location technology. It provides a simple API so that you can
    specify requirements—such as high accuracy or low power—at a high
    level. It also optimizes the device's use of battery power by caching
    locations and batching requests across apps. For more information about the
    ideal ways to request location, see the Getting the Last
    Known Location
    training guide.

  • Wake
    are mechanisms to keep devices on so that they can perform
    background activities. Avoid using wake locks because they prevent the
    device from going into low-power states.

  • To reduce the number of device wake-ups, batch network activity. For more
    information on batching, see the Android training on
    Optimizing Downloads for Efficient Network Access

  • WorkManager schedules
    tasks and lets the system batch operations. This greatly simplifies the
    implementation of common patterns, such as waiting for network connectivity,
    device charging state, retries, and backoff. Use WorkManager to perform
    non-essential background activity when the device is charging and is
    connected to an unmetered network.

  • For more information on how network activity can drain the battery, and
    how to tackle this issue, see Reducing Network Battery Drain.

Benchmark battery use

Benchmarking your app’s battery use in a controlled environment helps you
understand the battery-heavy tasks in your app. It's a good practice to
benchmark your app’s battery use to gauge efficiency and track changes
over time.
collects battery data about your apps, and
Battery Historian
converts that data into an HTML visualization.

more information on reducing battery use, see the Android training on Optimizing
Battery Life

Read article
Connectivity for billions  |  Android Developers

Over half of all users worldwide will experience your app over a 2G
connection. To improve their experience, optimize for low-speed
connections and offline working by storing data, queuing requests, and handling
images for optimal performance.

Here you can find some tips on how to accomplish these things.

Optimize images

There are a number of ways to make images easier to download. These include serving WebP images,
dynamically sizing images, and using image-loading libraries.

Serve WebP images

  • Serve WebP files over the
    network to reduce image load times and save network bandwidth. A WebP file is often
    smaller in size than its PNG and JPG counterparts, with at
    least the same image quality. Even using lossy settings, WebP can produce a
    nearly identical image to the original. Android has included lossy WebP support since
    Android 4.0 (API level 14: Ice Cream Sandwich) and support for lossless,
    transparent WebP since Android 4.2 (API level 17: Jelly Bean).

Dynamically size images

  • Have your apps request images at the target rendering size, based on the device specification,
    and your server provide appropriately sized images. Doing this minimizes the data sent over the
    network and reduces the amount of memory needed to hold each image,
    resulting in improved performance and user satisfaction.

  • User experience degrades when users have to wait for images to
    download. Using appropriate image sizes helps to address these issues.
    Consider making image size requests based on network type or network
    quality; this size could be smaller than the target rendering size.

  • Dynamic placeholders such as
    pre-computed palette values
    or low-resolution thumbnails can improve
    the user experience while the image is being fetched.

Use image loading libraries

  • Your app should not fetch any image more than once. Image
    loading libraries such as Glide and Picasso
    fetch the image, cache it, and provide hooks into your Views to show
    placeholder images until the actual images are ready. Because images are
    cached, these libraries return the local copy the next time an image is

  • Image-loading libraries manage their cache, holding onto the most recent
    images so that your app storage doesn’t grow indefinitely.

Optimize networking

You can enhance the user experience by providing an optimal
network experience.

For example, you can make your app usable offline, use

and Room,
and deduplicate network requests.

Make your app usable offline

  • In rural location and less affluent areas, it’s
    common for devices to lose network connectivity. Creating a useful offline
    state means users can interact with your app at all times. Do this by storing data locally,
    caching data, and queuing outbound requests to action when connectivity is restored.

  • Where possible, apps shouldn’t notify users that connectivity has
    been lost. It’s only when the user performs an operation where connectivity
    is essential that the user needs to be notified.

  • When a device lacks connectivity, your app should batch up network
    requests—on behalf of the user—that can be executed when
    connectivity is restored. An example of this is an email client that allows
    users to compose, send, read, move, and delete existing mails even when the
    device is offline. These operations can be cached and executed when
    connectivity is restored. In doing so, the app is able to provide a similar
    user experience whether the device is online or offline.

Use Room to fetch and cache data

  • Ensure that your app stores all data on disk using a database or similar
    structure so that it performs optimally regardless of network conditions.
    Use the Room persistence
    to cache data in a local database, and use
    WorkManager to update
    that cache when the device has a network connection.

  • Apps should cache content that is fetched from the network. Before making
    subsequent requests, apps should display locally cached data. This ensures
    that the app is functional regardless of whether the device is offline or
    on a slow or unreliable network.

Deduplicate network requests

  • An offline-first architecture initially tries to fetch data from local
    storage and, failing that, requests the data from the network. After being
    retrieved from the network, the data is cached locally for future
    retrieval. This helps to ensure that network requests for the same piece of
    data only occur once—with subsequent requests satisfied locally. To
    achieve this, use a local database for long-lived data (usually
    android.database.sqlite or

  • This architecture also simplifies an app’s flow between offline and
    online states as one side fetches from the network to the cache, while the
    other retrieves data from the cache to present to the user.

  • For transitory data, use a bounded disk cache such as a DiskLruCache.
    Data that doesn’t typically change should only be requested once over
    the network and cached for future use. Examples of such data are images and
    non-temporal documents like news articles or social posts.

Fine-tune data transfer

There are several ways in which your app can adapt to network conditions to provide a
better user experience. For example, it can prioritize network requests to minimize
the user's waiting time for information. It can also detect and adapt to slower network
speeds and changes that may take place in the network connection.

Prioritize bandwidth

  • You shouldn't assume that any network that the device is
    connected to is long-lasting or reliable. For this reason, apps should
    prioritize network requests to display the most useful information to the
    user as soon as possible.

  • Presenting users with visible and relevant information immediately is a
    better user experience than making them wait for information that might not
    be necessary. This reduces the time that the user has to wait and
    increases the usefulness of the app on slow networks.

  • To achieve this, sequence your network requests such that text is
    fetched before rich media. Text requests tend to be smaller, compress
    better, and hence transfer faster, meaning that your app can display useful
    content quickly. For more information on managing network requests, visit
    the Android training on Managing Network

Use less bandwidth on slower connections

  • The ability for your app to transfer data in a timely fashion is
    dependent on the network connection. Detecting the quality of the network
    and adjusting the way your app uses it can help provide an excellent user

  • You can use the following methods to detect the underlying network
    quality. Using the data from these methods, your app should tailor its use
    of the network to continue to provide a timely response to user actions:

  • On slower connections, consider downloading only lower-resolution media
    or perhaps none at all. This ensures that your users can use
    the app on slow connections. Where you don’t have an image or the image is
    still loading, you should always show a placeholder. You can create a
    dynamic placeholder by using the
    Palette library
    to generate placeholder colors that match the target

  • On devices powered by Android 7.0 (API level 24) and higher,
    users can turn on the
    Data Saver setting, which helps minimize data use. Android 7.0
    extends ConnectivityManager to detect Data Saver
    settings. For more information about this feature, see
    Data Saver.

Detect network changes, then change app behavior

  • Network quality is not static; it changes based on location, network
    traffic, and local population density. Apps should detect changes in
    network and adjust bandwidth accordingly. By doing so, your app can tailor
    the user experience to the network quality. Detect network state using
    these methods:

  • As the network quality degrades, scale down the number and size of
    requests. As the connection quality improves, you can scale up your
    requests to optimal levels.

  • On higher quality, unmetered networks, consider
    prefetching data
    to make it available ahead of time. From a user
    experience standpoint, this might mean that news reader apps fetch
    three articles at a time on 2G but fetch twenty articles at a time on
    Wi-Fi. For more information on adjusting app behavior based on network changes,
    visit the Android training on
    Monitoring the Connectivity Status

  • The broadcast
    is sent when a change in network
    connectivity occurs. When your app is in the foreground, you can call
    to receive this broadcast. After receiving
    the broadcast, you should reevaluate the current network state and adjust
    your UI and network use appropriately. You shouldn't declare this receiver
    in your manifest, as it's unavailable in Android 7.0 (API level 24)
    and higher.
    For more information about this and other changes in Android 7.0,
    Android 7.0 Changes

Additional resources

To learn more about supporting a variety of connection speeds, view the following

Blog post

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