This is a Camera GPRS/GSM Shield, which is use the newest A6C module , A6C module is not only have GSM/GPRS function but also can take picture.It supports GSM/GPRS Quad-Band (850, 9001800/1900) network. Also, it supports voice calls, SMS messages, GPRS data service and take picture by software. You can use it make a simple phone.
SIM808 GPRS/GSM+GPS Shield is a GSM and GPS two-in-one function module. This module can do just about everything, like make and receive voice calls using a headset or an external 32Ω speaker+electret microphone, send and receive SMS messages or send and receive GPRS data (TCP/IP, HTTP, etc.).