Abstract: An information processing apparatus (10) includes a display (110), a housing (120), and a wireless relay apparatus (130). A control unit is provided inside the housing (120). The control unit includes, for example, a central processing unit (CPU), and performs various pieces of arithmetic processing and control processing. One example of the control processing is control of the display (110). The display (110) is mounted to the housing (120). The wireless relay apparatus (130) is mounted to any surface in surfaces of the housing (120). As one example, the display (110) and the wireless relay apparatus (130) are each mounted to a side surface of the housing (120).

Abstract: In a purchase management system using a self-checkout register, pieces of information, which are respectively registered by individual terminal devices, are shared among a plurality of customers. A terminal device capable of acquiring item identification information of each item to be purchased first acquires a cooperation ID. Next, the terminal device shares the information in real time with a cooperative terminal device that is another terminal device and includes the same cooperation ID.