AT&T and T-Mobile USA have signed an agreement to enable roaming on their networks to customers of both companies in areas impacted by Hurricane Sandy, where capacity is available and for subscribers with a compliant device. AT&T and T-Mobile customers will be able to place calls as they normally would, but their calls will be carried by whichever network is most operational in their area. This will be for AT&T and T-Mobile customers with no change to their current rate plans or service agreements even if the phone indicates the device is attached to the other carrier's network. T-Mobile and AT&T both use network technology based on GSM and UMTS standards, which allows for this sharing of voice and data traffic.
