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 ...

All modern iPhones and iPads now use nano-SIM cards. Unfortunately, this can be a bit of a problem for anyone switching from an older device, because the nano-SIM is much smaller than the micro-SIMs ...

If you are one of the many impatient Apple fans from outside the US who have imported a 3G iPad, you will no doubt be more than familar with the lack of micro-SIM cards available on the global market.

T-Mobile is now offering a micro-SIM card for customers wanting to use unlocked iPhone 4 handsets on its network. This move shows that T-Mobile is not only embracing unlocked iPhone 4 users, but may ...

Even when you've got your hands on your iPhone 4, you still needs a SIM -- but not just any SIM: you need a micro SIM. Read on for more SIMnanigans Richard Trenholm was CNET's film and TV editor, ...