Abstract: Search and retrieval of information shared between members of a social mobile networks is facilitated. The search returns results in an order that is based on relevance measurements unique to each member. A comprehensive map of the interactions and behaviors that take place between the members of a social mobile network is discovered and maintained. Such maps are used to assign a unique relevance measurement for each member of each social mobile network.

Abstract: [PROBLEM TO BE SOLVED] To reduce a server load when synchronizing data between a client and a server. [SOLUTION] A client 10 sends a synchronization request 41 containing an anchor point to a server 20. The server 20 sends synchronization information 42 to the client 10, which synchronization information including change profile information on data updated between the anchor point and a boundary point and change profile information on a change log after the anchor point. Based on the synchronization information 42, the client 10 sends a download request 43 to the server 20, and the server 20 sends download information 44 to the client 10 in response to the download request 43. The client 10 registers data contained in the download information 44 to a client database 11.