Astrobuster

Space arcade with realistic physics.
You have space ship and must defend Earth.
Destroy asteroids and aliens, collect upgrades, then find alien base and blow it.
Leave your suggestions on improving in comments.

This game has paid version without any Ads = $1,00
http://market.android.com/details?id=com.astrobuster.paid
market://details?id=com.astrobuster.paid