Carriers operate under one of two types of networks: CDMA or GSM. Out of the four biggest carriers with their own network, AT&T and T-Mobile run on GSM , while Sprint and Verizon Wireless use CDMA.
Carriers operate under one of two types of networks: CDMA or GSM. Out of the four biggest carriers with their own network, AT&T and T-Mobile run on GSM , while Sprint and Verizon Wireless use CDMA.