Assisted GPS (A-GPS) is a technology that enhances the performance of traditional GPS by using network resources to help a device determine its location faster and more accurately. Instead of relying solely on satellite signals, which can be slow to acquire or weak indoors, A-GPS uses data from cellular networks or Wi-Fi to assist in positioning.

Secure User Plane Location (SUPL) is a standardized protocol used by mobile devices to communicate with SUPL servers that provide this assistance data. These servers supply the device with satellite orbit information and other location aids to speed up GPS lock times and improve accuracy.

In iodéOS, a patch to avoid leaking device identifiers (IMEI, IMSI) and phone number to SUPL servers while maintaining A-GPS functionality is implemented, and is now intergrated upstream in LineageOS.