I was looking only for wrist-phone and the Gear S works perfectly fine, I can get almost 3 days stand-by mode if I turn off GPS, 3G, wifi and bluetooth. I want to be able to use GPS/3G/Wifi/Bluetooth if I need to, but I mostly . That's what I have phone or tablet for. Receiving or making phone calls significantly reduces the amount of battery life though. It's just the stand by time. I have 2 phone numbers and I am using one phone number for emergency only for family and it's in the Gear S. Regular phone calls are going through my mobile.
