We've had a few conversations on HN about how QWERTY may not be optimal for mobile swiping, but it's better than the layouts optimized for typing. Dvorak, with all the vowels on the left hand home row, would be terrible for swiping, what with all the English words just a vowel away from each other.

As it is the UIO vowel complex is a frequent problem with swiping. I'd like to see U and O moved away from each other, in theory.