G-Switch is set in a seemingly futuristic setting, where you control G-Switch man equipped with gravity-switching boots. It is a side scrolling puzzle-platformer played using only a mouse button, with gameplay similar to Canabalt. Each click makes G-Switch man change from running on the ground to running on the ceiling. Miss a given platform and you disappear into the ether (well, game over), and start again in the last checkpoint.

The one-button gravity switch mechanic allows for a very fast-paced game. In the main game mode you have to complete 8 checkpoint sections. In Endless mode you have the challenge of beating your high score, in levels which are different each time you play. There's also a multiplayer mode for up to 6 players on one keyboard.