Some owners of Apple's new iPhone 4S have been hit with SIM card error messages, even if they are connected to a CDMA carrier that does not use SIM cards. One reader ...

The subscriber identity module -- SIM -- contains the information used to connect to your wireless carrier's network from your iPhone 4. If you are planning to resell your company's iPhones, you ...

While Sprint’s initial batch of iPhone 4S handsets were sold unlocked, allowing you to swap out your Sprint SIM card for a SIM card of your choice, that will no longer be the case. From today, ...

Apple recently seeded a second revision of its iOS 5.0.1 firmware, and besides decrypting key files that aid in the legality of a Siri port, the update seemed to bring nothing new to the table. Some ...

What is a SIM card used for? A SIM card, or a subscriber identity module/subscriber identification module, is a tiny memory card that contains unique information and is linked to a particular network ...

If you’ve bought an iPad with 4G/cellular capabilities (we discuss whether that’s a good idea in our 2015 iPad buying guide) or a new iPhone, you need to buy and install a SIM card. Here, we explain ...