Fun fact for the first apple keyboard layout on the first iphone, the touchscreen hadn't the resolution to tell appart which letter you meant to type in, so it changed dynamically the "hitboxes" of the letter buttons when you typed a certain letter. (for instance if you typed the letter "i", the hitbox of "t", and "n" were changed to be bigger, because there is a high probability you were hitting those next. Here is an article that talks about it : https://www.cnbc.com/2017/06/26/creation-of-the-first-iphone...
>the touchscreen hadn't the resolution to tell appart which letter you meant to type in
Is that really true? My memory of the original iPhone's touch screen is that it was pretty much pixel-accurate.
The article mentions that the keyboard wasn't accurate enough: "But by early 2006, the iPhone keyboard still didn’t have the accuracy Apple needed to ship the phone." I don't think that means the screen wasn't accurate; all it means is that the original iPhone had a small screen, so the buttons on the keyboard were tiny, and hitting them precisely was difficult. That's why the hit boxes of more likely keys were enlarged.
I think OP is misremembering about the reason for the hit boxes.
The base reason is the size of the keyboard compared with the size of thumbs and the imprecision of thumb typing. Adjusting the hit boxes results in a better error rate. It isn’t because of the resolution of the screen or touch detection.
FUTO keyboard actually has an option for this (enabled by default) called "Smart key-hit detection". It adjusts hitboxes based on dictionary predictions for what you just typed.
im fairly sure gboard does the same thing. it will bias towards certain subsequent keys based on the current input. im sure there's a whole bunch of tricks keyboard apps use to make typing "feel" accurate.