The interaction service is a means of communication that improves trade relations between the mall and visitors using mobile communications technology WAP and Bluetooth, as a new business alternative, and without operator’s network using the mobile phone. The proposed system of interaction, allows the exchange of information from a potential pool of buyers among visitors to a shopping center and the administration of the various shops, through the cell phone. The system consists of a mobile application in J2ME, the access points, Bluetooth server, and Web server with applications to mobile devices.