To make them explode, you will have to tap a group of at least 3 identical bubbles.
New bubbles are generated and periodicaly inserted at the screen bottom, and you loose if one bubble escapes at the board top.
Bubbles are inserted faster depending on your game level and as time goes on. A fourth bubble type appears at the eighth level.
You earn bonus points if you remove a large amount of bubbles by one stroke and an extra large bonus if you remove them all.
To pause or quit the game, tap the screen top line, then choose "quit" to finish the current game or "resume" to proceed with the game.

Enjoy the game...