I am having extremely good battery life on my 6, I am actually suprised how good the battery is and performance.
The thing is when I get a new iPhone I always set it up as new, but I have everything still backed up I just put the photos on manually, and brand new install of all the apps I use, notes, etc, all that manually, doesnt take me long either.
I feel like people who use recover from a older iPhone going to a new iPhone always brings some kind of battery bug glitch .
The battery life is pretty dam awesome on the 6 for me (Verizon), I suspect some apps are probably draining the battery more then usual since they aren't fully updated yet to iOS 8, plus iOS 8.0.1 is coming soon so quirks will be ironed out fast
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My 6 is acting just like my JB 5 as far as battery. It drains like the gas gauge on my old GTO under hard use. That is to say very fast.
100% this morning. 68% as I type this 2 hrs later. Lots of web and txt during that time.
location services on? push/fetch settings? There's actually alot of battery saving options in iOS
little things like turning off Vibrate on ring helps if you don't mind no vibrate on ring ( i dont ) and bunch of other things.
some apps arent fully updated yet and probably arent as efficient as they should be yet but .