One of the few apps that lets you create custom keyboard layouts (vs. just recoloring)! Only problem is you can't rearrange keys, making it way too hard to just add some number keys to the top, etc. So any minor edits basically require starting from scratch. Also would be nice to be able to change key height and create special keys like for tab, delete, arrows, return, date entry, etc. like in CoolWriter. Finally there's no manual and the UI has confusing, unlabeled icons so it takes a while to get used to. Best customizer I've found so far, but still has a way to go.

Not very intuitive? Sure. Worth it? Most certainly!