First up, if you were expecting Space Balls to be based on the classic Mel Brooks movie of the same name, I'm afraid this one isn't. Don't go away just yet though, because you'll still be able to have fun.
The aim of Space Balls is to defend your little planet from relentless hoards of colored balls that try to encircle you. To do this you need to fire your own colored balls at them from a rotatable cannon. If you can make a line of four or more balls of the same color then these balls will disappear and set the whole pack of invaders back a bit.
Space Balls is one of those games that are very simple to control yet can become impossibly difficult to master. You do get help, in the form of a meter that shows you which color ball is next to be fired, but after a while the action becomes so fast that it's impossible to keep up. This is even the case on the easiest of the three difficulty settings.
As for the graphics in Space Balls, they're bright and well drawn with a real 3D look to the balls. I was a bit disappointed with the irritating music, but luckily you can turn this off.
You might find Space Balls gets a bit repetitive after a few levels, but it's still a great time-waster to play on the bus.