Q: iPhone 5S getting incredibly hot and high battery usage after iOS 8 update

I had no problems at all with the upgrade to 8, didn't do 8.0.1 but on Sunday I applied 8.0.2 to my devices (iPhone 5S, iPad Mini, iPod Touch 5th gen).  No problems at all until this morning, and only with the iPhone.

Using my 4G I updated four apps and downloaded a book from the ibook store.  Went to ibooks to read the book, read the first chapter and ibooks crashed.  Opened the book again, back to the start and found that my setting to not show books in the cloud had reverted to showing them, went to chapter 2 and started reading, crash.  Re-booted (held down off and on switches) and tried again.  Got a bit further before the app crashed.  This time the phone was very hot, something I have never experienced before other than the minor heat when re-charging the phone.  Shut the phone down completely and left for 20 mins to cool down.  Turned on again and returned to ibooks, same book, read a bit, crashed and phone becoming very hot within maybe two minutes.

Phone off, cooled it again, turned on and tried several apps none of which heated the phone.  Opened ibooks again, deleted the book I had downloaded just in case that was the reason it was heating.  Turned phone off again without doing anything else, back to ibooks, read another book and although it took a little longer, the device heated up.  Battery meanwhile had drained considerably since I first turned the phone on, visibly dropping by 1% for each page I read of the book.

Device currently charging via battery doctor.

No problems at all on my iPod or iPad - I considered replicating the above on one of these but decided against it as I don't need two devices overheating.

Even after updating to iOS 8.0.2 directly from iOS 7.1.2 I'm having alot of bad issues on my iPhone 5S 32 GB Gold. And the experience is getting worst. Please help me at my thread. And please feedback to Apple ( For those having the same issue ) .. Here's my thread and please help me

My just upgraded iPhone 5S ( 8.0.2 ) is suffering from over-heating and all the apps are crashing ... I had to cancel my call just after 10 minutes as it was so heated up ...

I have the same exact problem with my iPhone 5s 32GB.  Since upgrading from iOS 7.1.2 to iOS 8 (and now 8.0.2), my battery drains very fast and the phone heats up more than ever.

I close all my apps on a regular basis, but the problem persists. Here are some of the steps I tried (not listed in any particular order):

- turned off Location Services for apps that don't need my location (which is most of them)

- turned off Background App Refresh for apps that don't need it (which is most of them)

- performed several hard reboots and regular power off/restarts

- turned off all System Services except Find My iPhone

- turned off Send Last Location for Find My iPhone

- turned off Share My Location

- reduced the screen brightness

- set Auto-lock to 1 minute

- set my email to Fetch every 30 minutes instead of Push

- synced with iTunes on my laptop

After all those steps (and probably a few I can't remember), my battery is still draining way too fast and the phone is heating up too much.

at this point guys i think i need serious lectures on how to downgrade,the problems are getting worse on my iphone 5s Gold,cant connect to wifi for 2days now,my phone hangs like there's no tomorrow especially when a call come in or ending,apps crashing and phone still very heated,am just so frustrated here,feel like crying cause now my phone is just there looking at me,please please please am crying out to apple to help me

someone should please respond to me,lots of issues here with my 5s and am going ragga,cant connect to my wifi for 2days,any time i try once i click on the wifi menu it hangs,just now i tried switching off my phone and realised it doesnt work any more,when i press down the power botton nothing happens and after sometime i hear the sound as if am locking the phone.............guys please help out a brother

Can you include my name in the response please, I have the exact same problem.

Please let me know if apple have an answer for you.

Hi Most likely problem is your battery is failing.

I had exactly the same problem, so went onto the apple support via the web and spoke to someone using their chat service.

I explained the situation regarding the battery life and how hot it gets.

He asked me for an email that's linked to my iphone to send a diagnostic tool that sends him my battery status report. Once you have followed the prompts it sends it back to him to examine.

low and behold my battery was failing.

im booked into a authorised apple repair shop to replace my battery under warranty

I hope this helps

In my case it is unlikely to be the battery, my phone only gets hot when I open iBooks.  I've opened most of the  other apps on the phone (8 pages of them including nested apps so quite a lot) and none of them heats the phone if left running for around 5 minutes, only iBooks.  When I had a book open in iBooks the battery was draining approximately one per cent in one minute.  If it were the battery then the device would be heating up even if I just have the home screen open.

The only other thing I am noticing that is 'wrong' with the phone is app updates. Just prior to noticing the iBooks problem yesterday morning I had updated some apps via the phone, and there was nothing unusual happening at that time.  I then opened iBooks and downloaded a book that I had just purchased and began to read it.  Then the phone began to heat up.  Some time later in the day another app needed updating, I did so via the phone but the app store badge remained in place and if I opened the app store app the 'open' button first showed 'update' and then quickly flicked to 'open'.  Today there were three apps to update on the phone but I had already downloaded these to PC so decided to synch them across to the phone.  When I opened the App store app they showed 'open' but the app store icon had a badge showing 3 apps needed updating, I re-opened app store, touched open against one of these apps and it began downloading rather than opening.

I've just synched my iPod Touch which has 5 apps requiring updating - the apps have not synched across to the Touch.  Going to the App section in the device screen on iTunes each app shows 'update' so I've had to manually select each - and the same is happening re updates, the badge number remains and the apps revert to 'update' although touching the 'update all' button has now changed them to 'open'.  Turned the iPod Touch on/off a couple of times and re-opening the App store app a quick flash of 'update' and then revert to 'open' but the badge remains showing 5.

I notice in the settings for iBooks (settings menu rather than within the app) there is an option to 'use mobile data' which was on so I have turned it off which means I get a prompt each time I open ibooks to turn it on.  That option is not in iBooks on iPad or iPod Touch (as of course they do not have mobile data) - no idea if this is a new option but I've not noticed it before and no idea what it actually does.

Can't say I am impressed at the sheer amount of time I, and many others, are now spending trying to get our devices to work properly as a result of this OS update.  Apologies if some of what I am listing is 'rubbish' but I'm putting here anything that is happening in the hope that when Apple do respond to our queries (made by the feedback link) they will visit here and look see what users have reported.

Is My CPU Working Fine...? Running 8.0.2..  iPhone 5s.

Afraid my PC won't show those png files, I only see the file name.

5 hours and 3 days on standby is REALLY good o_o....

My iPhone 5S on 7.1.2 had a max of 10 hrs and 1 day of standby! And now, at 8.0.2, I am not even getting close to 5 hrs usage v_v....... Like, right now, I'm at 46%, 3 HRS 23 MIN (Usage) and 19 HRS, 9 MIN (Standby). So I think your battery life is superb (compared to my iPhone 5S running both 7.1.2 and 8.0.2).

Since updating to ios8.2 my iPhone 5s is ruined too...

Is anyone else experiencing a really hot phone? the battery is draining when its not being used (all apps closed) and the phone is HOT! Contacted apple and they said to look at the battery usage - which isn't looking like its showing whats really draining the battery.

On top of this my data usage is through the roof! its loading constantly... and going to cost me a fortune.

Bad form apple.

After a month using iOS 8 and updated to 8.0.2 (not 8.2 as you wrote) and still experiencing the same high CPU usage, fast battery draining and hot iPhone (in the top right area on the back). Reviewing the apps that eats more battery appears the Mail app in first place, after having used it to answer a couple of mails with 65% usage. In second place appears Home/Lock Screen with 13%. But the high CPU usage starts when using other apps like Safari to wrote this note for example.

This behavior never happened in iOS 7 since I bought my 5S on september 2013. All started with iOS 8. So something is taking to much cpu usage in all iOS base apps, to do similar tasks than in iOS7.

I would expect Apple already has done the job and in the next iOS 8.1 update this nightmare will be completely solved, and the 5S will get back the original battery duration on a normal usage day.

The next OS update is Monday so I'll report back after I have installed that.

The battery usage reading really seems to depend on which app you have used the most in the last 24 hours/7 days.  In my case as I had been testing out iBooks as it was the only app making my phone heat up, the battery usage at the time for that app was high.  I don't feel that it is actually an accurate measure of something going amiss with the device, just that you can judge which or the apps you use a lot in, say, a 24 hour period, uses a lot of power.

Monday 20 October sees the release of OS 8.1 so I suggest waiting for that and see if that fixes the problems.  Today I've swapped from iPhone 5S to a 6plus which I am currently setting up  (it came with 8.0.2 on it).  I am holding out on adding anything to ibooks (which is the only app that was heating my 5S) until the update.