Game play involves piloting deep sea diver down by jumping on the differently colored bubbles. To jump from bubble to bubble and guide diver to desired direction player has to tilt phone left or right. You can jump only once on each bubble before it disappears. If you run out of bubbles to jump on, you can tap the screen anywhere to get some more. But be careful, all user generated bubbles come from your own air tank and you can easily to run out of air before you even notice.
When looking for new deeps to conquer look out for dangers of sea: there are octopuses, jellyfish and fake gray bubbles that will make your dive harder or even dangerous. The deeper you go the darker it gets, when you get really deep you will need collect light-bulbs to remain visible.