Hi Wendy.Hu,
thanks for your answer!
On the store, there aren't GPS/GPRS/GSM shield with the pinout compatible with the Arduino Leonardo embedded on the LattePanda board :( .
Today I purchased the GPS/GPRS/GSM shield SIM808. It could work on the Lattepanda board?

Hi Wendy.Hu! :)
Thanks for your answers!
For space reasons,I would like to use only the Arduino Leonardo embedded on the LattePanda to connect the SIM808. If I use another Arduino Board I need to use an USB port (it is too precious and I wouldn't use it :D ). For work I need to use all the USB ports without any HUB usb.
Could I connect the SIM808 on the Arduino Leonardo using the Rx (pin 2) and Tx (pin 4) and the power?

Hi Wendy.Hu!
It works in USB debug mode using AT commands!
Connection Scheme:
Vin: +12V (external power)

LattePanda's GND connected with the SIM808's GND
D10,D11 (tx and rx pins) connected on rx and tx pins of the SIM808.

In the Arduino sketch I defined a SerialSoftware object on these pins: all the AT operations work like a charm :-)

Thanks for your support!