Pretty damn good.
Really good dude. You know, for being just the first one out (at least i hope) is really good, nice gameplay, actually original and really well structured. As everyone else says, it needs more RPG elements, like leveling up, having xp, maybe choosing the abilities you have for each of your plains or stuff like that. It looks promising as far as i can see. It's really good, and i'm trying to achieve 4 stars on every level :P
Hope you don't make me wait too much dude, because, this looks great :)