Hi @ dayleeo, i do not have to say anything but a ingenius, humane, useful and smart idea and product and hunt.
Anyone, who first remember for to allow blind humans typing on a computer certainly, do it thing great work.
Where are the sign characters on the screen - where are blindman fingers?
When he moves them and put them in another place again - there are signs under their fingers ... And so again.
This is so done that blind man does not have to look for it keyboard "but where the blind man has dropped his fingers ... means he does not look for a keyboard, but the keyboard asks for him ... this is probably the best solution for the first contact with the letters ...
The voice app notifies the "songwriter" what he has written (navigation) so that he knows at all times as long as he has written (and what is written).
It probably will not work for mobile phones - because of the size of the screen but also this is a huge step in introducing into the more normal life of the blind.
There is still a lot of work, but, and the longest way begins with the first step.
Really good hunting.

Good luck with him.