อัปเดตเมื่อ Mar 8, 2017
Added explicit 'App Switch' button which replaces old 'Menu' button (and 'Menu' now has its own keycode). So, for now there are two logical buttons which usually implemented in one physical button. Which one is used in your device depends on manufacturer. For example, in Nexus devices it is 'App Switch' keycode and in Xiaomi it is 'Menu' keycode. You should manually set appropriate logical type to remap physical button.
Also debug mode added.