Is this good battery life?
What do you think about the battery performance on 8.1.2?
Just replace the battery. I've had my 5 for almost two years now everything is working fine except the battery started to drain real fast. I replaced it, super easy. Literally just watch a youtube video. Bought a spare battery from zeetron.com, mainly because I'm located in new york and I knew the shipping would be faster. Now it like its a new phone.
What if AppleCare says the battery is still healthy? Could a battery replacement still help?
I'm not 100% positive. But I say why not, if you like to gamble. The new battery would only be $12.99 investment. So its not like your spending a ton. And if it doesn't fix it then put the original battery back in and maybe return the battery you bought.
I recently purchased this one http://www.zeetron.com/iphone-replacement-battery/
You will need a couple of tools, but their relevantly cheap. Also if you do decide to replace it yourself, there is a adhesive on the oem battery just use a heat gun or hair dryer to help pry it up easier.
I haven't gone thru and read all 33 pages of this thread. How old is your phone?
What is about the battery on iOS 8.1.3?
My wife's phone had a step change (worse) in battery usage about a week ago. I made all the standard setting changes, and did a erase and restore from backup...all with no effect. The usage list always had "home and lock screen" as the dominant process consuming battery by a long way.
Eventually erased and set up as new phone, and it is transformed...better than it ever has been.
After the erase it did take a couple of days while Photos and Mail showed as high users as background activities, syncing large mail and photo collections (beta lib is on), but once up to date it has been great.
I did have a call to Applecare who did the diagnostic test and reported battery was fine so it had to be a software problem.