My Galaxy S6 just updated to Lollipop 5.1.1 and now when I open CS I get a black screen until I hit the overview button. However at that point I just select the CS window and the game will be fully loaded. Not that worried about it since it is so easy to fix, but thought I should report it anyway, especially since 5.1.1 is going to keep rolling out to compatible devices and others might have the same issue.