Some interface adjustments may be required when making applications Fire OS 5 compatible. If interface elements are not functioning as intended it may be because there have been changes to the methods those elements are referencing. Check to make sure that the app is following the current best practices for Android Lollipop. 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 the latest version of Unity 3D can be found here: https://unity3d.com/unity/whats-new.
Keywords: soft key, button, Unity