Yeah I believe it is likely the case that the RePhone consumes a bit of current when in “OFF” mode. I have now drained 2 LiPo batteries down past the point of no return by leaving them plugged into the unit for a couple days (making sure the unit was OFF each time I left it). The RePhone’s USB charging circuit will no longer charge the batteries as it senses that they are too low in voltage.
Are there “low power” functions that can be accessed (then programmed into the RePhone) via the ArduinoIDE?