You can turn off data on an iPhone all at once, for specific apps, or by turning on Airplane Mode through the Control Center. Here's how to do each.

It’s a good idea to turn off data roaming on your iPhone if you want to avoid using data while traveling internationally. Here's how to do it.

Changing physical SIM cards on your phone is always a fiddly business. First, you have to root for the little SIM tray tool ...