If you’re thinking of moving to a new network, and want to keep hold of the same iPhone, you may hit a snag: the device is locked to your current carrier and can’t be used with any other company.

A SIM card, or subscriber identity module card, is essential component of any phone. It connects your device to a cellular network and stores vital information, including your phone number. Many ...

Yesterday we told you about a service that will unlock your iPhone 4 by altering its IMEI number. While that sounds good, at $180 it's pretty expensive and there's no guarantee Apple won't be able to ...

One of the promoted specifications on the new Apple iPhone 4S is the "world phone" capability, but it isn't quite the world phone that many international travelers who use GSM phones are used too.