I have to admit that I never played Super Blast, but the sequel has entertained me for a little while now. It's a straight-up shooter game with a nice, easy control scheme. All you do is tilt your device to aim and shoot, and you can occasionally tap the screen to clear it with a bomb. It's a tried-and-true premise, and it works well. My one complaint is that it's hard sometimes to tell how your ship is doing and/or when the enemies are actually taking damage. On bosses with large amounts of health, you usually have to just fall back on watching the numbers, and that's a little more boring than it could be.
The game's power-ups are quite fun, and the graphics are excellent, featuring almost whimsical 3D alien models with extremely high resolutions that look excellent on the Retina Display. There are plenty of particle effects to go around, and when you do it just right, cutting through the well-rendered bad guys is really satisfying. Game Center integration helps you keep the fight going as well.
Super Blast 2 is just US$0.99 on the App Store right now, and while it's somewhat simple, it's definitely worth a download.