Hi Ben!
There are rumors that ninty is considering to build their own android/ios controller accessory. Could you please show them how it should be done? 
Holder for a phone, a nice grip and not focused on compactness would be on my list of features. It should be like holding an original gameboy. Good grip, large and confortable.
Analog control would not be a must IMHO.
Other than that, great show great work keep it up!
Cheers