I ordered one of these boards (hasn't arrived yet) but I couldn't find a spec sheet or something that could tell me how to power it from something else than the USB port.
I see it has some pins named 3V3, 5V and Vin. Since it can be run from USB (5V) but seems to use 3.3V internally, I assume it has an onboard voltage regulator. Is it safe to connect a battery to Vin? What's the allowed range of the voltage connected to Vin? Is it possible to connect a 1 or 2 cell LiPo?