Battery life issues on iOS 8

hi. after updating to a new operating system, always do a deep cycle. in other words, drain it till the phone dies. leave it like that, for about 20 mins, to let a bit of extra power drain out. plug it in, and charge up to full. leave plugged in, once fully charged, for about 2 or 3 hours. then take it off once more, and drain it completely again. then, after charging it up, and leaving it for another 2 hours once full, use it as normal. this helps the battery circuits report the right information once more. do this about once a month to keep the battery in good condition. also, as a side note, when do you charge your phone. every night? or only once it gets down to a certain level. and if the latter, what level do you start charging the device at.

also, how old is your device, and what model is it. it could simply be that the battery is beginning to die, if it's an older device.

i haven't noticed any major extra battery drain over iOS 7, having followed this process.

What is the best way to do a complete drain on the battery? Do you just not charge it until the phone shuts off, or are there settings or things I can do that will help drain the battery quicker?

I have noticed on both my iPhone 5s and 5th generation iPod Touch, both purchased last December, and both running IOS 8.0.2, that sometimes they burn through a charge like there's no tomorrow and at other times a charge seems to last forever. As best as I can remember, my usage of the devices remained about typical for me, so, in theory, battery life shouldn't vary so wildly.

Turn battery draining apps like GPS apps and such on. Let the phone completely die. Totally recharge and let it die again. Completely charge, turn those apps off. That should do it.

Hi Callum and all.
I am also facing battery issues on an iPhone 5S running iOS 8.0.2. The phone was purchased last January and had no battery problems on iOS 7. I am still facing battery issues even after making a full restore and following the list of suggested comments above.

Hi all, I experienced the same battery problems as others have mentioned. I found that rebooting the phone, and letting the battery drop to about 35% every day before charging it seems to have fixed the problem.

The iPhone 5 first generation battery replacement program. You said you got yours on first launch. copy this link into your browser. enter your country and your phones cerial number which can be found on your phone or whilst connected to iTunes:
https://www.apple.com/ca/support/iphone5-battery/

This isn't as much about battery life as it is about the battery meter.

After doing some iTunes browsing and buying a couple of songs on my iPod Touch 5g, before putting it away, I checked the charge on the battery on status bar, it said 36%, so I decided to plug it into the charger, when I did, it announced that it was charging the battery and that the battery had a 52% charge on it.

Not even a minute had gone by between the two readings. Weird!

I just got bit by this "bug?"

Last night, just before going to bed, I checked the battery level on my iPhone 5s and it showed a 66% charge, so I just locked the screen and didn't plug it into the charger. This morning, I used it for about ten minutes to check email, the locked the screen. Later while checking on some information for something I was working on, within a few minutes, I got the 20% battery warning, so in about 15 minutes of light use over an eight hour period, it consumed about 45% of the battery.

Considering that this iPhone 5s is less than a year old, seen light use, and I'm careful to not excessively recharge the battery, letting it drop to between 20% and 30% before recharging, I have my doubts that it's a problem with the battery needing to be deep cycled. Especially when I never seen battery consumption like this while running IOS 7.

I suspect that IOS 8 is going into some routine or loop that doesn't allow the processor to go into idle as much as it should when the phone isn't in use.

I have an iPhone 5 running 8.1. I was hoping the 8.1 would fix my battery issue but it did not. Using the below method though, I think I improved it.

I was following the suggestion to decycle the phone and noticed how the battery meter would jump up and down while trying to drain my phone. It showed I had 1 percent left but I was still able to play a 45 minute video clip from Netflix. LOL. Anyhow, this is what I did.

Best way IMHO to drain a phone is to play a video or give it to a kid and let them play a video game. Once the phone is dead, wait a few minutes then try to turn it on. If it turns on, try to drain it again until it turns off. Do this until the phone will no longer turn on. For me, I did this about 15 times. Charge it up and decycle it one more time.

I think the problem is the OS not knowing how much power is left in the battery thus it shuts down the phone prematurely.

David