Here's a COPY from a post in another forum. A lot of fellows in that forum reported positively to the solution suggested by Markbob917.
Hope it helps.
Mar 21, 2013 9:04 PM
Last night I updated my iPhone 4S to a iOS 6.1.3 and now it drains my battery in extremely fast manner. As I started signing in to write this question from my iPhone I already lost 13% of my battery. I never had a problem with a battery and ive been using iphones since the first one. i miss my morning class because of it because my alarm clock didn't because my phone was dead. Please fix it or have no choice but buy Samsung GS4
iPhone 4S, iOS 6.1.3
This solved my question by Markbob917 on Mar 23, 2013 12:32 PM
I can confirm mine is now fine.
Go to settings
Mail, contacts, calendars
Go into iCloud and turn all switches to OFF one by one make sure you save all to iPhone though not just delete
Then go to each other mail account and repeat this procedure again making sure you select keep on iPhone not the delete option
Once they're all turned to off check your calendar to see if everything is missing off it and then you need to do a hard reset by holding the home button and the on/off button until the phone turns itself off.
Once it's come back on go back into settings and mail and turn each switch (or each you want) back to ON.
Then make sure all your apps are closed lock the phone and leave it for 30 mins and then check the battery hopefully if like mine it shouldn't of dropped at all
This worked for me hopefully it will work for others out there
See the answer in context
I have this question too (25) Categories: Basics Tags: ios, update, battery, drainage, died, 6.1.3
I came across this thread: https://discussions.apple.com/thread/4907710?start=0&tstart=0
The "fix" described in that thread is not terribly invasive or difficult (although many of my email accounts would not turn off and stay off, requiring several reboots). I can't swear yet that this method works, but I've been off the charger for nearly a full day and still have 67% battery left, and the usage meter says 3 hours and 34 minutes (mostly wifi, but some 4G/LTE).
Post replies to this thread if you try this method...
This will sound crazy......I realized I had downloaded a new app the same day I had upgraded to 6.1.3.
Being suspiciuos of that app, I removed it this morning and 10 hours later it is still at a charge of 68%.
The app was a scanning app called REDLASER. Could be a coincidence but thought I'd pass it on.
Had the same problem of battery drain with my new iphone 5 , updated to 6.1.3. Could see the battery dropping fast every 5 mins.This is on day 1 of the purchase.
Have been going thru the fixes mentioned in MANY of the posts available.
My 2 cents on the subject :
1) Reset the network settings
2) Fully discharged the battery and did a full recharge to 100%
Got thru the day without having to recharge.
Got 14Hr 30 Mins from a full charge along with 1 Hr 45 Mins of Google Maps usage which used up 40% of battery.
This is without using 3G, I'm sure it will drain the battery faster.
Re Iphone 5 battery issue - My latest experience
I tried many things posted all over th net to resolve my battery problem. I thaught I had resolved it but last week I was in London and by 2 pm my battery was down to 25%. I walked into the covent garden Apple store. I waited one hour to see one of their experts. He tested the phone and said there is a fault with the battery. He gave me a new one on the spot and since then it has been perfect, I get 2 days of heavy use.
My conclusion is that , simply, they have an issue with the Iphone 5 battery
Not necessarily, all I am stating is my experience. I can see that many have the same problem and I suspect that they ciould have had a batch of batterries from a dodgy supplier.
A battery drain resulting in the phone not lasting 1.5 to 2 days is abnormal. The suggestions I have seen to tun this and that off are silly. Yes if you turn the phone off it will last a long time.
Based on my experience I would recommend all that have a problem to go to an Apple Store if they can or get the phone exchanged under warranty until they get one with a battery that works.
This is indeed the last apple product I will buy. I love the iphone 5. But what is the point without a battery. I'm seriously thinking a out relegating the 5 for home wifi use and go purchase a galaxy or android for out and about. I'm tired of monitoring the battery, tired of walking with extra batteries and just win disappointed. May Steve Jobs rest in peace. All his hard work is being undone by incompetence.