Ok, there is no way you get 40 hrs out of a charge. Maybe if you are 3g only or wifi only. Does the phone say LTE or 4G? There is a difference. Also, If you are not on LTE or turn your data off, your numbers are irrelevant. Nobody, well almost nobody, buys a smart phone and goes around with the data off. If your data is off or you are in 3g only area, of course you are going to have better battery life. I could probably turn all of my antennas off and use the phone for a paper weight and not get 40+ hours, but then what is the point. If you are 3g only or wifi only you need to specify. It is not possible to get these hrs in a LTE market using your phone fully. It just isn't possible. if it is, I got another bunk 920. I get 3-4% in true LTE standby and I have done everything.