[Object] To enable a user to simply and easily confirm update information of a plurality of pieces of content data handled by a plurality of various application programs without any troublesome operation. [Solving Means] A plurality of update information display cards (51) are aligned and displayed on a display screen (50). The update information display cards (51) displayed on the display screen (50) are associated with different pieces of content data, and update information of the content data is individually arranged on the corresponding update information display card (51). Moreover, the update information display cards (51) on which the update information of the different types of content data are arranged are aligned and displayed on the display screen (50) in a chronological order of the updates of the content data.