SIM cards are all around us, and with the continuing growth of the Internet of Things, spawning technologies like NB-IoT, this might as well be very literal soon. But what do we really know about ...

A multi-carrier GSM phone with two, three or four SIM cards. Dual-SIM phones are popular with global travelers who use local and foreign carriers as well as people who want a business and personal ...

(Subscriber Identity Module lock) A function in GSM cellphones that restricts the phone's use to a particular cellular carrier identified by a SIM card. SIM locks are used to ensure subscribers ...