I like the game. But considering that unlocking the third level requires at minimum 5000 worth of upgrades(assuming that speed 4 is enough to beat either of the first two levels in under 45 seconds), you make too little money per level. Assuming you beat the first level perfectly on the first try and assuming you make maximum amount of money each time you play the second level(440, since you can get maximum of 440 without doublejump) that requires the player to play the second level eleven times. That's just way too many repeats for the game to stay interesting for that long.
Also, the mute button seems to reset each time you exit a level.