Click a neighbour cell to get influence on its group. Click on another neighbour cells until you or you opponent get stuck. The most influence one wins the game. As easy as playing rock-paper-scissors for anyone that love a speedy puzzle-strategy games.
Click on your neighbour cells. Clickable ones will get highlight on it.
A context menu should be shown when right-clicking or, on touch devices, long-pressing in the game. This menu especially allows to play in full screen and control the volume.