A position of first cursor changes according to a position of thumb. A position of second cursor changes according to a visual line of a user. If a position of first cursor remains unchanged over a predetermined time period, the position of first cursor is fixed. If a distance between first cursor and second cursor has become longer, image G1 on display other than first cursor or second cursor is enlarged. If a distance between first cursor and second cursor has become shorter, image G1 on display other than first cursor or second cursor is reduced.