Wow I really had a lot of fun with this charmingly simple game!
+Simple and clean graphic design
+Good stage design
+Difficulty Increased at a very friendly pace
-The tutorial should pop up when starting the game, no exceptions! I nearly exited the game before even getting a chance to play it.
+/- More difficulty options per stage would nice. (faster speed?) Something that can contribute to the replayability of the game. Though I had fun, the game did end relatively fast.
Hope to see more! =]