Abstract: A mobile information server system is installed on mobile devices. When more than two mobile devices are carried by users, each of the mobile devices sends a geographic position and an IP address to a network location server to be stored and updated by the network location server. The network location server further analyzes the geographic position of each of the mobile devices, and sends the geographic positions and the IP addresses of other mobile devices that are nearby the mobile devices to each of the mobile devices, respectively. And then, the mobile devices obtain and display the information published by the other mobile devices through software protocol to accomplish the function of local business service. The network location server delivers the geographic position and the IP address, but not other information, and each of the mobile devices plays a role of an information server.