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 ...

Conflict is brewing in the mobile world over the adoption of a new, smaller standard for the SIM card — the chip in each GSM phone that dictates which network you connect to and your cellphone number.

The SIM cards that fit into those tiny slots in your cell phone and tell your cellular network to whom your calls are to be charged come in four different sizes. With the only real difference between ...