Blink word

This app was created to assisted communication with people for whom it is difficult to talk but who can blink.
You ask "Left?" - the person doesn't blink.
That means Right. Then list the lines: First? Second?.. F? G?
Soon the person will remember where the letters are and they won't have to look at the screen.
All entered words are remembered by the app.
The longer you use the app the eaiser communicational process will be.