olemus
nutitelefon vm mobiilseade, mis töötab ainult
ta tarnija antud algse SIM-kaardiga;
alates 2013. a. on USAs kinnistusest vabastamine ebaseaduslik
=
a mobile device that can only be used with a particular SIM card and is incompatible with devices from other manufacturers

ülevaateid
https://www.techopedia.com/definition/29602/locked-down-device-ldd

https://www.techopedia.com/definition/24280/unlocked-cellphone