1) Please, change the hero's color. It took me five seconds to find where i was on the 2nd level.
2) I think there should be a way to do a short jump, like : pressing the jump button quickly = little jump ; pressing the jump button a long time = long jump
3) You should do something about that invisible platform, like stopping the yellow arrow thingy when touching the invisible platform.
4) On the third level, if your are below the pink elevator, you become one with the wall. http://imgur.com/a/2mIwA