The display can be powered directly from a Raspberry ... Other features of the Raspberry Pi 500 computer keyboard include an ...

If you're looking for a rapid trigger keyboard to cut fractions off your reaction time, and like the idea of an extra little screen to display in-game information, this is an excellent choice ...

My guess is that FlickType will work for you no matter your screen size. If you ever need to send messages from your wrist, FlickType Keyboard is the way to do it.