Although cell phones have changed significantly in the last few decades, they still need a SIM. Some phones have moved to eSIMs, but many still use physical SIM cards. If you have a working phone, ...

For many years, mobile phones received cellular service through a physical SIM (subscriber identity module) card that connected your handset to your phone carrier. These physical SIM cards made it ...

A dual-SIM setup lets you use one phone to make and receive calls and texts from two numbers. It's also super convenient and can save you serious cash when traveling. We show you how to use two SIMs ...

Cingular mailed me a new SIM card with a letter stating that I should take out the old chip and put in the new one. So I took out the old one, put in new one, called to activate it, and the phone ...

Are you trying to switch phones or carriers? You might need to swap SIM cards for that, and we can understand how confusing this process can be if you haven’t done it before. Today we’ll show you ...

An unlocked phone is the key to getting service from an alternative carrier. Here's how to check if a phone is unlocked.