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 ...

In a first for US wireless carriers, Sprint and Verizon Wireless will allow iPhone 4S customers to unlock their mirco-SIM card slots, which enables use on wireless networks around the world, reports ...

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 ...

Contrary to initial reports, the Sprint version of the iPhone 4S will not come with an unlocked microSIM slot allowing customers to pop in international SIMs; it will be able to roam on international ...

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 ...