Hi,
As I understand you don't need an app developer for this project, only someone to give you a concept on how to handle multiple-choice quiz questions in a mobile app without using a keyboard.
As a game designer I focus on user engagement, usability and the flow experience of the users.
My proposal consists an online discussion with you (e.g. skype) where I can understand the problem better and give you a few ideas to that problem.
Please note that I am out of office till Friday 17 June, however we can have this discussion on that day.