Since Android7.0 (N), android support multi-window mode.
1. Configuring Your App for Multi-Window Mode
AndroidManifest.xml android:resizeableActivity=true support multi-window android:resizeableActivity=false not support multi-window "App doesn't support split window" if Overview key long pressed android:supportsPictureInPicture=true support PIP 2. Multi-window mode does not change the activity lifecycle switch from multi-window to not support, or vice vesa onStop/onDestroy/onCreate/onStart/onResume 3. Related API isInMultiWindowMode() isInPictureInPictureMode() onMultiWindowModeChanged() onPictureInPictureModeChanged() 4. Check task stack adb shell am stack list 5. modify resource related res/layout, res/layout-land,drawable/,drawable-hdpi/,drawable-ldrtl/, drawable-nodpi/, drawable-xhdpi/, drawable-xxhdpi/
6. Reference
https://developer.android.com/guide/topics/ui/multi-window.html https://developer.android.com/training/tv/playback/picture-in-picture.html