A social network helps mobile device users purchase applications for their devices and to purchase new mobile devices. The network utilizes information from a user's friends to effectively “recommend” applications and mobile devices, and in particular recommend mobile devices based on the applications recommended. The phone numbers of a user's contact list may be scanned by the system to identify friends of the user. A friend network database stores the user's information and friends' information throughout the network and supplies the information to an application store where users may download applications or purchase mobile devices. The information supplied by the database includes the applications and the mobile devices of friends or friends of friends. In response to a user inquiry, the store displays the amount and/or identities of friends and/or friends of friends who have downloaded a particular application or own a particular device.