Shoot the planes. Sounds simple. There's only one problem. The planes are shooting at you!! And they will crash into you and take away your health, if you know what I mean!
Time-ups, Power-ups, Health Packs, Enemy Eliminators all will help you succeed!
Special thanks to the artists for the public domain images of the Cannon, planes and spaceships used in this app.
Image Sources: Cannon Wing Yu - clkr.com, ClipArtLord.com, vector.me, OpenClipArt.com.