What makes the gameplay unique, is not the changing gravity alone, but the fact that the "planets" don't actually pull you towards them. The gravity changes only when the player character touches a surface. This opens up a lot of possibilities in level design and gives the player much more freedom.
In the later worlds, when the player has been familiarized with the basic gameplay, we introduce "gravity fields", which enable us to mix traditional platforming and gravity-defying platforming in interesting ways.
The team reports the game has been in development for 6 months and they have experimented with several iPhone style control schemes but still settled on a simplified button system.
The game has been submitted and should be coming out soon.