A mobile terminal capable of operating in a plurality of position tracking modes. The mobile terminal comprises: 1) a Global Positioning System (GPS) unit capable of receiving GPS signals from a plurality of GPS satellites, wherein the GPS unit is further capable of operating in i) a device autonomous fix (DAF) mode, ii) a server-computed assisted fix (SCAF) mode, and iii) a device-computed assisted fix (DCAF) mode. The mobile terminal also comprises: 2) a network transceiver capable of communicating with at least one terrestrial wireless network; and 3) a controller capable of controlling the operating mode of the GPS unit. The controller is capable of transitioning the GPS unit between the DAF mode, the SCAF mode, and the DCAF mode.