The devices page within the PanatrackerGP web portal will display the last-known IP address of the registered handhelds as a convenience. This handheld address is obtained from the webserver's knowledge of the handheld client as it communicates with the server.
If the handheld is part of a network that is behind a NAT router, the webserver will see the gateway IP address only and cannot penetrate into the internal network. NAT or Network Address Translation helps improve network security by reusing IP addresses and shielding the details from resources outside the internal network. In this case, the network "hides" the details of the handheld IP address from the Panatracker server and we cannot display the exact handheld address.