• Aim by moving your finger or the mouse. The dotted line shows the bounce off the side walls.
• Shoot by letting go, clicking, or pressing Space.
• Three or more of the same colour touching pops the whole group.
• Anything left hanging once the group is gone falls too, and falling bubbles are worth double.
• The spare bubble in the corner can be swapped in - tap it, or press S.
• The rainbow bubble takes the colour of whatever it lands against.
• Miss too often and the wall drops a row. Let it reach the red line and the round is over.

Keyboard: ← → aim, Space shoot, S swap.