Kevin Hill2, I have never used a device with LTE and with my not active usage, my previous devices were discharging for several days. LTE network is new in my country, and it's very rare in terms of coverage. The signal strength is one bar(of 5!) constantly, very weak signal and the phone spending more energy to sustain LTE connection! And I don't want that. So I think LTE connection is the problem, besides, my father has lumia 640 with 2500 mAh battery and it lasts for several days with quite active usage with location turned on, frequent calls and 3G network.
gordonfink, yes, I want to choose from the list(wich I can find without problem on my previous lumia 900 and my father's lumia 640) the network - 2G, 3G or 4G which will be active at the moment. For example 2G is old with EDGE internet but it covers all my places, I want to turn it on and it won't drain the battery at all.. But this setting is just gone, I know where it should be, and it's not there :crying:
I turned off data first day, but the phone still uses LTE network( I can read "My operator's name - LTE" in the upper right corner).
May be I missed something or AT&T blocked that feature? And what's going on with this network switching on Windows Phone 10?