Graphics: 4.25/5 Vivid, interesting, and colorful. Very nice to the eye. The only real flaw is that you always play with the same city in the background, which is a little annoying, but it's okay.
Sound: 4.5/5 The game sounds good. There are 10 tracks, and the game costs $10. The songs for the most part are pretty fun and interesting, but where are the bonus track packs?
Control: 4.25/5 Takes time to get used to, but it's a very simple idea. Press the buttons on screen as the scroll past the line on top.
Fun: 4/5 Boom Boom Rocket is a game of potential. It's $10 for 10 songs, so it's not a BAD price, but it probably should be lower, and the game isn't very deep. A track pack would be great, and it'd be nice to see one available soon.
Achievement Difficulty: 5/10
Pretty easy achievements here. One of the few you'll likely struggle on would be to get an A on any song on hard. You can get 95% of the notes, use your power-ups, too, and still only get a B. Also another tough one to get, would be to unlock all the fireworks. 10 songs, 3 difficulties, means 30 fireworks. And some of the songs on hard are VERY tough. You'll still be able to get quite a few achievements.