Applications may need to be optimized to ensure Fire OS 5 compatibility when setting how activities should react to being paused and resumed. If a blank screen appears when re-launching the application, it is most likely due to a conflict with the Android Runtime (ART).
Check to make sure that the app is following the current best practices for Android Lollipop, as several of the media playback methods have changed since its release. Pay special attention to the onPause() and onResume() methods as well. If the application is utilizing Unity 3D, confirm that it has been built using the latest version of the game engine.
Information about the some of the Android methods that have changed can be found here: https://developer.android.com/about/versions/android-5.0-changes.html.
Information about pausing and resuming an Activity in Android can be found here: http://developer.android.com/training/basics/activity-lifecycle/pausing.html.
Information about the Android Runtime (ART) can be found here: https://developer.android.com/guide/practices/verifying-apps-art.html.
Information about the latest version of Unity 3D can be found here: https://unity3d.com/unity/whats-new.
Keywords: media play back, blank screen, launch, Lollipop