A cellular phone communicates data with an information provision apparatus connected via a packet network. A control unit obtains an information management apparatus identifier for identifying an information management apparatus within the packet network which is an intermediation at the time of the data communication carried out with the information provision apparatus further connected via an external network among the information provision apparatuses, determines whether the identifier added to the data at the time of the data communication is coincident with the information management apparatus identifier, and calculates a data amount at the time of the data communication carried out with the information provision apparatus connected via the external network. A storage unit stores the calculated data amount.