technology
IMEI
The unique serial number identifying a phone to the network — used for allowlists, blocklists, and activation checks.
The IMEI (International Mobile Equipment Identity) is a 15-digit serial number that uniquely identifies a phone's hardware to the network — separate from your SIM, which identifies the subscription.
Carriers use the IMEI to decide whether a device may activate (Verizon's allowlist works this way), to block stolen phones, and to identify devices network-side. Practical dumbphone relevance: before buying an unlocked or imported phone, run its IMEI through your carrier's "bring your own device" checker — it is the definitive answer to "will this phone work on my network?"
Related Terms
View all →Location tracking
The continuous recording of where your phone — and therefore you — goes, via GPS, Wi-Fi, Bluetooth, and cell towers.
Metadata
Data about your communications — who, when, how long, from where — which reveals more than most people expect.
VoLTE (Voice over LTE)
The technology that carries voice calls over 4G — and the certification a phone must have to place calls on modern US networks.