The GPRS/GSM Shield provides you a way to use the GSM cell phone network to receive data from a remote location. The shield allows you to achieve this via any of the three methods:
Short Message Service
IComsat is a GSM/GPRS shield for Arduino and based on the SIM900 Quad-band GSM/GPRS module. It is controlled via AT commands (GSM 07.07 ,07.05 and SIMCOM enhanced AT Commands), and fully compatible with Arduino / Iteaduino and Mega.
This module measures only 1.75"x1.6" but packs a surprising amount of technology into it's little frame. At the heart is a powerful GSM cellular module (we use the latest SIM808) with integrated GPS. This module can do just about everything.