A data management apparatus for managing a plurality of data items output by a plurality of communication devices that output data, the data management apparatus comprising: a data processing apparatus; and a charge amount determination apparatus, wherein the data processing apparatus includes: a storage that stores an acquirer identification of a data acquirer who acquires data, in association with a device identification for identifying each of the plurality of communication devices and an application identification of an application, and stores the plurality of data items output by the plurality of communication devices in association with the device identification; a request acceptance means for receiving a data acquisition request including the acquirer identification from a data acquisition apparatus; and a communication control means for extracting, based on the acquirer identification included in the data acquisition request, data output by the application on a communication device corresponding to the device identification and the application identification stored in the storage in association with the acquirer identification, among the plurality of data items received from the plurality of communication devices via a relay apparatus, and transmitting the extracted data to the data acquisition apparatus, wherein the charge amount determination apparatus includes: a charge amount determination means for determining a charge amount for the acquirer identification based on a combination of the device identification and the application identification associated with the acquirer identification. a data processing apparatus; and a charge amount determination apparatus, wherein the data processing apparatus includes: a storage that stores an acquirer identification of a data acquirer who acquires data, in association with a device identification for identifying each of the plurality of communication devices and an application identification of an application, and stores the plurality of data items output by the plurality of communication devices in association with the device identification; a request acceptance means for receiving a data acquisition request including the acquirer identification from a data acquisition apparatus; and a communication control means for extracting, based on the acquirer identification included in the data acquisition request, data output by the application on a communication device corresponding to the device identification and the application identification stored in the storage in association with the acquirer identification, among the plurality of data items received from the plurality of communication devices via a relay apparatus, and transmitting the extracted data to the data acquisition apparatus, wherein the charge amount determination apparatus includes: a charge amount determination means for determining a charge amount for the acquirer identification based on a combination of the device identification and the application identification associated with the acquirer identification. a storage that stores an acquirer identification of a data acquirer who acquires data, in association with a device identification for identifying each of the plurality of communication devices and an application identification of an application, and stores the plurality of data items output by the plurality of communication devices in association with the device identification; a request acceptance means for receiving a data acquisition request including the acquirer identification from a data acquisition apparatus; and a communication control means for extracting, based on the acquirer identification included in the data acquisition request, data output by the application on a communication device corresponding to the device identification and the application identification stored in the storage in association with the acquirer identification, among the plurality of data items received from the plurality of communication devices via a relay apparatus, and transmitting the extracted data to the data acquisition apparatus, wherein the charge amount determination apparatus includes: a charge amount determination means for determining a charge amount for the acquirer identification based on a combination of the device identification and the application identification associated with the acquirer identification.