Bluetooth Electromagnetic Field, radio waves from the fitbit is not that bad it is very low in fact that they're exempt from the evaluations required for other RF devices like cell phones.   But my concern is for cumulative, wearing it 24/7, since they've added sleep tracking.  I would want to take advantage of that, wearing it 24/7 but i don't want WIFI/bluetooth ON while i sleep while wearing fitbit.  Samsung gear sport can turn off bluetooth or any signals coming out from the watch but it's horrible at sleep tracking. I would like to go back to fitbit, but with the bluetooth/wifi always ON is keeping me from wearing it. Please give us users an option to have an airplane mode so we can turn off WIFI and Bluetooth.  Thank You