Comet Crash is pretty good.
It's a tower defense game where waves go both ways.
The art is very alike to Total Annihilation / Supreme commander on PC. Clean polygonal units with primary colors. The (back)ground is a still image but since the units and all are 3D it flows really nice and smoothly around screen. Like in Pixeljunk Monsters you are a presence on the map. In this game it's a engineering space ship, you can get shot down if you're not careful.
Soundside is good with some relaxed techno and crisp (but moderate) laser pew-pew effects and such.
Building your own waves is pretty cool. Different type of units like scouts, tanks and 'hammers' that stun the enemies wave. I've yet to gain the more exotic units like aircrafts and stealthers. You can haul in random meteors with your space ship gravity beams for more resources (your towers will shoot them down). You can build special structures that only let your troops out and so forth.
While Savage Moon is seemingly a bit more meaty I find this one more elegantly executed and the offensive aspect makes it more interesting.
