Abstract: A mobile terminal server (40) distributes information on an item put up for auction at an auction venue and bid price information to a smartphone (11), and every time the information on the item is changed, transmits empty data as well as a bid price that is automatically raised by a server (30) until it reaches the lowest acceptable price. The smartphone (11) receives the distributed bid price information and displays the bid price on a display unit (113). If the displayed bid price is a desired price, the user selects a participate mode, and places a bid by operating a place bid key (B3). The smartphone (11) maintains communication with the mobile terminal server (40) as long as empty data is transmitted. This prevents communication from being suspended and prevents a delay in display.