Cellular phone having navigation device, correcting value initializing method, and navigation function

A navigation device includes a measuring unit to measure the current position; a geomagnetism sensor that is provided on a predetermined main unit, and is to detect geomagnetism; an orientation calculation unit to calculate the orientation of the main unit, upon setting correction values for correcting detection values of the geomagnetism, based on the detection values and the correction values; a presenting unit to present measurement results by the measuring unit and the calculation results of the orientation to a user; an operating state switchover unit to switch between a normal operating state that executes the presenting processing and a suspended state that maintains a portion of processing state while stopping at least the calculation processing of the orientation; and an initialization processing unit to initialize the correction values, in the case of having switched from the suspended state to the normal operating state by the operating state switchover unit.