SIM lock


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SIM lock

(Subscriber Identity Module lock) A function in GSM cellphones that restricts the phone's use to a particular cellular carrier (a particular SIM card). SIM locks are used to ensure subscribers finish their service contracts when the phones are heavily subsidized by the carrier. SIM locked phones may be unlocked by entering a code.

Apple's iPhone brought the SIM lock into public view because of its original exclusivity in the U.S. with AT&T. However, iPhones were readily "unlocked" by hackers both in and outside the U.S., not only to use a different carrier, but to customize their appearance and download applications even before Apple debuted its App Store. In addition, Apple allowed the GSM iPhone to be sold without the SIM lock in Australia, Taiwan, Hong Kong and other regions where locked phones were either prohibited or a recipe for marketing failure. See SIM card and iPhone jailbreaking.
References in periodicals archive ?
DIS will in addition deal with corporate requirements by offering combined services of SIM lock free devices with the network and service its partner provides.
If the SIM Lock status for your device shows locked, you can unlock your phone through your carrier for a nominal fee or sometimes free of charge if you have completed the contract.
To have SIM lock removed, the customer must take their device to any docomo Shop in Japan and sign a waiver acknowledging that certain services and features of the device and network might be disabled when another operator's SIM card is used.
Robust hardware security blocks for implementing SIM lock, flash lock