Core app quality

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 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.

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.

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

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

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.

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.

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

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.

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.

• 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.

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.

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.

The app requests permission to access sensitive data (such as SMS, Call Log, or Location) 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.

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

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.

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

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

Starting August 2021, the use of Android App Bundles will become mandatory for all new apps in the Google Play store.

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.

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

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

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

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