Is it possible to create a screen overlay where taps on the background will pass through to the app below? My goal is to create a floating button that can be dragged around the screen and occasionally display some information, then allow it to float over other apps like games. I want to be able to move the button around the screen, but still play the game behind it. I'd want to create an HTML page with a transparent background and be able to have it sit on top of other apps and only block where there are visible elements on the screen. Can this be done?