A microchip and a GPS device serve different purposes. A microchip is a permanent form of identification that contains a unique identification number linked to a database with the owner's information. It does not provide real-time location tracking but helps reunite lost pets when scanned by a shelter or veterinarian. A GPS device, on the other hand, actively tracks a pet's location, often in real-time, allowing owners to monitor their pet's movements. While GPS provides location data, it lacks the permanence and identification benefits of a microchip.