The game itself is fun and the extreme levels are actually challenging however, the wait time for each song is ridiculous, largely dependent on ad time and a lot of times not providing any ads at all for hours which gives you no play time. Developers should definitely come up with a better system or at least tell us how long we need to wait to play the next song. If they want money, leave it to box purchases. The game traction will decrease if players have to purchase just to play.