I'd bet the device only registers power on/off from the port to know when to start collecting data. Everything else is probably done from an internal or cellular synced clock and accelerometers within the device. It may use cellular service to send a coded text at intervals containing the basic data. All in all probably way lower on the tech pole than your average smart phone. I'd just worry it could be a drain on your battery to keep the device alive if/when sitting unused for extended periods of time. But that's the only problem I could see it causing.