Abstract: A portable GPS/radio unit (10) communicates over a wireless radio network (12) with at least one other such unit (10A-10E). The unit (10) may transmit radio signals over the network (12) indicative of the unit's location and receive similar radio signals from other such units. The unit (10) is operable to display an indication of the distance between two or more units, an indication of the amount of time that has elapsed since location data was last received from another unit, a track log or track back information for another unit, and an indication if the unit (10) is about to lose communications with another unit. The unit (10) also may be operated to gather and transmit to other units location data corresponding to way points. The perspective or vantage point from which location data and other information is viewed may be selected or changed by the user of the unit (10).