About SIM lock
Mobile phones can be locked and also made to accept just SIM cards belonging to a particular network. This is done as such that GSM phones will work just on the network of the carrier.
SIM-locked telephones are normally locked to a carrier when the carrier sells the gadget at a low cost so as to pull in new customers to its service.
A few network providers offer a SIM unlock uption to their users after a specific amount of time has passed. Unlocking the GSM phone should be possible by entering a special code which is created dependent on the phone’s IMEI number.