Edit: That was sort of tongue-in-cheek, but I could see being able to run your finger around the screen and when you hit a 'dot' there's a haptic response.
https://github.com/Hendekagon/MorseCoder
-- it's very basic
Edit: That was sort of tongue-in-cheek, but I could see being able to run your finger around the screen and when you hit a 'dot' there's a haptic response.