In brief, I am looking to buy a device, which can send SMS to a person's cell phone from a microcontroller.
I found a device Arduino GSM Shield, which can send SMS from microcontroller but 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
The link for the list of cell phone service providers frequencies is
Please confirm me if I will be able to use Arduino GSM Shield to work with AT&T or T-mobile
Please reply as son as possible