A T9 layout condenses the entire alphabet into just 9 massive active keys. This tight 3x4 grid fits perfectly within the natural sweeping arc of a human thumb.
The biggest struggle with modern smartphone keyboards is the "fat-finger" problem. A standard QWERTY keyboard crams 26 letters into a tiny horizontal space. t9 keyboard emulator better
He turned back to the screen. A new message was typing itself, the numbers appearing without his input: A T9 layout condenses the entire alphabet into