1. A portable terminal device, comprising: a user interface for enabling user input into the portable terminal device; a network connection unit configured to establish a connection to a computer network; a local network connection unit configured to establish a connection to a local network different from the computer network, the local network being a network locally defined among the portable terminal device and at least one other computer device; and a processing unit configured to upload a prescribed information regarding the computer network that is necessary or utilizable in operating an application program by being connected to the computer network and that is setup data or input data for the application program stored in said at least one other computer device, from said at least one other computer device connected to the portable terminal device via the local network through the local network connection unit, carry out a prescribed processing for automatically setting the setup data or the input data into the portable terminal device without requiring any user operation using the user interface, in a form utilizable by the application program on the portable terminal device, according to at least a part of the prescribed information, and execute the application program by using a result of the prescribed processing and being connected to the computer network through the network connection unit; wherein the processing unit obtains the prescribed information related to a specified type of application program that exists in said at least one other computer device, by transmitting to said at least one other computer device via the local network a first request for obtaining an identification information for identifying said specified type of application program, receiving a reply containing the identification information from said at least one other computer device via the local network in response to the first request, transmitting to said at least one other computer device via the local network a second request for obtaining the prescribed information according to the identification information contained in the reply, and receiving the prescribed information from said at least one other computer device via the local network in response to the second request.