I wish I had a smartphone, but alas. I'm into games, and actually getting into designing some myself though so I'll happily provide some feedback. I'm not familiar with your experience in app/game development (being such a newb here), so don't take my tone as preachy. I tend to "turn off my mind, relax, and float down stream" when I write, and it comes out the way it comes out. 
First, Faceo wins this thread for suggesting that there be 7 levels (I love that story). Definitely try to do that.
You might want to try setting ...