Indoor positioning systems (IPS) differ from outdoor positioning systems like GPS primarily in their technology and environment. While GPS relies on satellite signals, which are ineffective indoors, IPS uses technologies like Wi-Fi, Bluetooth, RFID, and ultrasonic beacons to navigate within buildings where satellite signals are unavailable or unreliable.
Additionally, indoor systems often require more precision to navigate complex indoor spaces compared to the relatively open environments navigated by outdoor systems.