Fully Featured Arduino Quad-band GSM/GPRS Shield which also features GPS! Based on the SIM808 module. Great for IoT and tracking projects, this shield allows you to communicate over the cellular GSM networks while also capturing GPS position data.
SIM900A GSM/GPRS Dev Board Module With Antenna. The SIM900A, a module from SIMCOM, is an ultra compact cellular wireless module. The SIM900A Module is a complete Dual-band GSM/GPRS wireless unit and is very popular with makers, who benefit from small dimensions and low cost.