I am not sure if Arduino GSM Shield is compatible with the technologies of our local service providers , like AT&T or T-mobile, as it does not use EDGE or UMTS technologies to send data.
The link for the list of cell phone service providers technologies is
List of United States wireless communications service providers - Wikipedia
Someone please confirm me if I will be able to use Arduino GSM Shield to work with local cell phone service providers,i.e AT&T or T-mobile
thanks a lot in advance
siddhartha