What network are you on?
I'm in the UK, on Three, carrier settings are 17.0.
I'm going to tweet them to see if that's the latest version or not.
I am on Verizon Wireless LTE in the US. My carrier settings are also 17.0.
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Have faith, I expected the poor battery life I'm experiencing. Therefore I'm not disappointed. Nothing will change until next model. More new improvements will be included next year. I have confidence.
I just don't understand how some of us can consistently get 4-5 hours of battery life while others can consistently get 7-8 hours and beyond.
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Yep, same numbers here - 5.5 hours. I'm wondering if it's worth pursuing with Apple and trying to swap my device out for another or to move up to the plus. Still, if I'm only getting 5.5 hours from the 6, then that put me at 7.5 hours or so with the plus. A measly two hour increase in battery life. Don't know if that's worth the tradeoff of having to carry a bigger phone around.
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I am on 3 Mobile...
I noticed that when I lower the screen's brightness the battery seems to last longer.
That's the thing, I just switched from an iPhone 5 and I don't feel any improvement yet. I know it might need a few charging cicles before I jump to conclusions.
My screen brightness is set at about 60%, which I don't think is excessive. I literally have every suspect configuration turned off (e.g. location, automatic updates, spotlight, background app refresh, parallax) and still I can only achieve 5 hours of battery life.
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Looks like this may be a solution.
"I spent several times in Apple Care Suport ( CASES 590332090 AND 590610977 at 03/20/14 ). An senior engineer guide d me to put my IPHONE 5S in DFU MODE and reinstall firmware! Further we created a new ICLOUD ACCOUNT because I realized that when ICLOUD was activied temperature increased so much! I make an appointment in Apple Store and in 10 minutes they conclude DFU MODE. I restarted using my new icloud account.After then my phone is normal now. Battery is during by 12-10 hours! I have 2 iCloud accounts now."
https://discussions.apple.com/thread/5377854?start=15&tstart=0