Shoot the aliens!
Get rid of all the aliens by matching the same color weapons.
Space Blast is a version bubble shooting where you need to kill all the aliens with their own weapons in order to save the humanity.
Just tap on wherever you want the weapon to go and match three of the same color to make them disappear. Keep doing that until you've cleared the screen completely. However, we have not been able to play, since it force closes every time we try to.