A SIM card, or subscriber identity module, is a small card in your cellphone that lets you place phone calls, send text messages, and more.

If you've just got your hands on a shiny new Sim card, congratulations. Switching your Sim (the chip that dictates your allowance) can unlock huge savings. Now comes the crucial step of activating it ...

eSIM is the latest sim card technology that allows you to access mobile networks without needing to get a physical sim card. Certain new phones such as Apple’s iPhone, offer the eSIM feature along ...

These two ways of connecting your phone to a cellular network are very different. We tell you about each and how you can switch from one to another.

Once you’ve activated your iPhone with your carrier, it should continue to work on the cellular network without any problems as long as you’re within range of a tower. Nevertheless, the vagaries of ...