Comment by makeitdouble

FTWIW the keys' hitboxes aren't at the displayed area, but at the expected landing area.

I'm slightly making up the exact bias, but for instance it will be assumed the user lands a touch slightly above the actual key, as the finger hides the target and Apple's heuristics expect some overshooting.

In comparison people used to the iPhone's heuristics might have a harder time on android.