Volume Buttons In-app use

Make the volume buttons in some way to be used as a use button, like when fishing is hard to press fish again and again and my volume buttons are very comfortable to be pressed, and other volume button to toggle split controls on and off very fast, cause mining is easyer with split controls, and fighting is easyer with normal touch interface! Or make the volume buttons cuscomizable, to bind them to any action the player want! And make the circle that appear on mobile when tou mine smaller, for a phone that circle si too big, and is hard to see what I am mining!