The Android Q platform includes behavior changes that may affect your app. The following behavior changes apply to all apps when they run on Android Q, regardless of 'targetSdkVersion'. You should test your app and then modify it as needed to support these properly, where applicable.
Make sure to also review the list of behavior changes that only affect apps targeting Android Q.
Non-SDK interface restrictions
To help ensure app stability and compatibility, the platform started restricting which non-SDK interfaces your app can use in Android 9 (API level 28). Android Q includes updated lists of restricted non-SDK interfaces based on collaboration with Android developers and the latest internal testing.
If you will not be targeting Android Q, some of these changes might not immediately affect you. However, while you can currently use non-SDK interfaces that are part of the greylist (depending on your app's target API level), using any non-SDK method or field always carries a high risk of breaking your app.
If you are unsure if your app uses non-SDK interfaces, you can test your app to find out. If your app relies on non-SDK interfaces, you should begin planning a migration to SDK alternatives. If you cannot find an alternative to using a non-SDK interface for a feature in your app, you should request a new public API.
To learn more, see Updates to non-SDK interface restrictions in Android Q and see Restrictions on non-SDK interfaces.
Wi-Fi Direct broadcasts
On Android Q, broadcasts related to Wi-Fi
Direct are no longer sticky.
If you app relies on receiving these broadcast at registration because they
had been sticky, your app no longer receives them. Instead, use the appropriate
get() method at initialization to obtain the information.
SYSTEM_ALERT_WINDOW on Go devices
Apps running on Android Q (Go edition) devices cannot receive the
SYSTEM_ALERT_WINDOW
permission. This is because drawing overlay windows uses excessive memory,
which is particularly harmful to the performance of low-memory Android
devices.
If an app running on a Go edition device running Android 9 or lower receives the
SYSTEM_ALERT_WINDOW permission, the app retains the permission even if the
device is upgraded to Android Q. However, apps which do not already have that
permission cannot be granted it after the device is upgraded.
If an app on a Go device sends an intent with the action
ACTION_MANAGE_OVERLAY_PERMISSION,
the system automatically denies the request, and takes the user to a
Settings screen which says that the permission isn't allowed because it
slows the device. If an app on a Go device calls
Settings.canDrawOverlays(),
the method always returns false. Again, these restrictions do not apply to apps
which received the SYSTEM_ALERT_WINDOW permission before the device was
upgraded to Q.
Warnings for apps targeting older Android versions
In Android Q, the platform will warn users the first time they run any app that targets a platform version lower than Android 6.0 (API level 23). If the app requires the user to grant permissions, the user is also given an opportunity to adjust the app's permissions before the app is allowed to run for the first time.
Due to Google Play's target API requirements, a user would only see these warnings if they run an app that has not been updated recently. For apps that are distributed through other stores, similar target API requirements are also being introduced in 2019. For more information about these requirements, see Expanding target API level requirements in 2019.
App usage
Android Q introduces the following behavior changes related to app usage:
UsageStats app usage improvements
Android Q now accurately tracks app usage with UsageStats when apps are
used in split-screen or picture-in-picture mode.
Additionally, Android Q can now track instant app usage.
Per-app grayscale
Android Q can now set apps to a grayscale display mode.
Suspension improvements
In Android Q, suspended apps are no longer able to play audio.