For me, I find this game way too easy. Perhaps some enemies, like shooting ones could ramp up the difficulty. But maybe you were going for an easy game, I don't know. Also for an infinite runner like this, audio can really put the game on a whole new level. Also some key features, required for games are missing, such as menus, etc.
I did like the art a lot though. Perhaps you could add on to it with a paralax background, or something like that.