I was thinking about the same idea since the first crossover rumours. they could release an android based handheld with games controlled with buttons and games only played with touch. then release an appstore for mobile devices with exact same games. new user would play touch only but at the same time they would see a massive list of unplayable games which they could play if they buy an extra nintendo gamepad.
but if they do this then I would like to keep backward compatible to ds / 3ds so the gamepad need a second screen and some kind of battery to boost smartphone gaming time.
look at this device, it exist for real:
the android handheld they could keep in it's 3ds fashion and for the phones they could release a gamepad which represents the lower parts of this device to turn the phone in a real handheld.
