Found this space shooter went free on App Shopper. Seems to have good reviews on iTunes. Haven't tried it yet (have to free up some space to DL) and can't seem to find too much on it here on TA. Anyway, here's the link: http://itunes.apple.com/us/app/the-void/id307867865?mt=8
It's an old game, but they just did a Retina update, very pretty. It's like Asteroids with some RPG-lite progression. Or Space Miner with a more "serious" tone.
I'm surprised this game didn't get more attention, given that Space Miner is so popular here. I've only just discovered it and quite enjoying it.