The first footage from Sonic Dash is here, the endless runner for iOS (and probably Android in the future).
The game is mostly what you would expect, quick-step left to right, collect rings, jump over obstacles and roll into enemies. It looks as if the only zones playable, at least for the time being, are Seaside Hill and Ocean Palace from Sonic Heroes, and a lot of the sound are obviously borrowed from said game as well. At the end of the trailer we also see a in-game real-money upgrade store.
SEGA, mind me asking, if you wanted a runner-game on mobiles, was it not possible to port Sonic and the Secret Rings? That game was a runner after all, just with a plot.