Depending on the phone the consumer chooses, his Straight Talk coverage in his home area could be the same as his coverage with a postpaid carrier. The greatest differences in coverage are in areas where the assigned network coverage is spotty, as Straight Talk does not allow roaming.
As of 2015, Straight Talk phones use a variety of other cellular networks to provide coverage, depending on the device the customer buys or brings to the network. Straight Talk assigns customers with any of the iPhone 4 models or the iPhone 5 to the Verizon network. Those with the iPhone 5s or 5c use the AT&T network. The carrier assigns other smartphones to Verizon, AT&T, Sprint or T-Mobile, based on the phone manufacturer and model.
Once the customer determines the network for his phone, he is able to determine coverage by looking at its coverage maps to determine if a smartphone is a good choice. When looking at the maps, customers should ignore any areas marked as roaming or where service is provided by partner networks.
While Straight Talk allows customers to bring their own phones, it does not activate phones for areas where the assigned network does not provide coverage. If a customer lives outside Verizon's coverage area and tries to import an iPhone 4, Straight Talk does not allow him to bring his own phone, but requires that he buy a new device.