This action took place in Brazilian supermarkets. It was a mobile game, which is based on the worldwide classic game Space Invaders, but in this case, instead of aliens we have stains. The users had to use their mobile phones in order to control and 'kill' the stains. There were two ways to connect with the game:1) either through bluetooth device2) or via a free call number, which connected to a server and linked both game & mobile phone. This connection was available for people who didn't have bluetooth.