Nice work on this game (one of the few I saw in development).
The visuals are really nice, the audio is well mixed and the concept is cool. The only real problem is the controls.
Personally I found them quite sluggish, which made timing jumps quite difficult. I also noticed that you move left and right around the circle but jumping kicks you out towards the edge. This adds some extra difficulty, which is fine, but I'm not sure whether that was intended.
Overall though, a really great game and I look forward to seeing where it goes in the future.