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 need to find out your iPhone's carrier without a SIM card installed, you can do so through the Settings app.

To remove the SIM card from your iPhone, you'll need to eject the SIM card tray with a special tool or paperclip.

Sareena was a senior editor for CNET covering the mobile beat, including device reviews. She is a seasoned multimedia journalist with more than a decade's worth of experience producing stories for ...

Anyone looking to add more than one number to their iPhone, maybe to keep work and pleasure separate or just to have multiple numbers on one device. Will be pleased to know that this is made possible ...

Have you found yourself unable to send or receive messages on your iPhone? Or are iMessages being sent from your email ...