To attain excellent operability by temporarily fixedly displaying a display range, shown slightly before, on one of two image screens when the other image screen is scrolled to display a map or the like.

During scrolling, a scroll quantity determination section determines whether a map displayed on the scroll image screen has been scrolled by a predetermined quantity by a scrolling section. Until it is thus determined that the map has been scrolled by the predetermined quantity, a display section for showing the contents before the scroll displays a map within a range stored in a storage section, on the auxiliary image screen.