Sand sand

I have bought an underwater phone case with bluetooth buttons. The buttons connects as a bluetooth keyboard. I can use the shutter (Enter) and Zoom (volume up and down). But there are also a button for switching camera (that emulates key "3") and start video recording (that emulates key "4"). I need an app that can be remote controlled by numeric keypad. OpenCamera settings documentation writes about Settings Manager having an entry with name "Remote control" which supports numeric keypad. But this...