cute game, reminded me alot of doodle jump
I think this could benefit from some kind of clear line at the bottom to make it visible that you will die touching it.
I think increasing difficulty would also do this game well along with maybe a more complex leveldesing or art . f.e a background wich changes depending on how high up you are.
I really like the way the cube looks with the 4 color sides eventhough it took me a bit to realize what exactly those do.
If done right this could become a very addictive mobile game! especially maybe if some kind of goals besides a highscore are implemented.