Your phone's SIM card allows the device to make calls, send texts, and connect to the internet. The SIM card provides a phone number that identifies your device on the carrier's network, whether it's ...

This is not as easy as it sounds — and it’s not common advice. But there’s a new warning for iPhone and Android users to ...

(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 finish ...