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

Hey everyone,
This is the first problem I have ever had with my iPhone.


I own an iPhone 5s and updated to iOS 8 late last night, my phone was fully charged this morning and is now down to 42% after only 1 Hour 37 Minutes of usage...


My battery life could last me a whole day (anything between 6 and 9 hours usage time), so this is a huge issue.


I have also had to remove my iPhone from its case and even turn it off in order to let it cool down, it got hot enough to feel through the case.


I am extremely disappointed as I was looking forward to the iOS 8 update,
and now all I am encountering.


Any suggestions is issues.or advice?

iPhone 5s, iOS 8, Public Release.

Posted on Sep 18, 2014 3:53 AM

Reply
115 replies

Sep 24, 2014 10:54 AM in response to LeeS7237

Please be careful of updating to 8.0.1!!!!
"

Apple has released an update for its devices to add HealthKit app support and to fix a number of lingering bugs from iOS 8, which was released September 17th.

iOS 8.0.1 has the following updates:

  • Fixes a bug so HealthKit apps can now be made available on the App Store
  • Addresses an issue where 3rd party keyboards could become deselected when a user enters their passcode
  • Fixes an issue that prevented some apps from accessing photos from the Photo Library
  • Improves the reliability of the Reachability feature on iPhone 6 and iPhone 6 Plus
  • Fixes an issue that could cause unexpected cellular data usage when receiving SMS/MMS messages
  • Better support of Ask To Buy for Family Sharing for In-App Purchases
  • Fixes an issue where ringtones were sometimes not restored from iCloud backups
  • Fixes a bug that prevented uploading photos and videos from Safari

We’re hearing, though, that the update has created problems for many iPhone users, affecting their ability to connect to a cellular network. iPhone 6 users are also reporting issues with Touch ID.

We’ve reached out to Apple and are waiting to hear back, but in the meantime hold off on pressing that “Update” button."



I am holding off on the update as I don't know if it will affect my phone, for those who want to update go ahead, but I thought this would be useful info for those who are paranoid of being one of the "1%" that got affected with certain disabilities when updating (like the battery drain when upgrading to 8.0)


SOURCE: http://mobilesyrup.com/2014/09/24/apple-releases-ios-8-0-1-with-healthkit-suppor t-but-hold-off-on-download/?utm_content=bufferd3e52&utm_medium=social&utm_source =facebook.com&utm_campaign=buffer


EDIT: PS, I'd like to hear experiences of those who did update to 8.0.1! Did your problems go away? Did more problems come like the ones from my source appear? Did the pre-8.0.1 problems persist and become worse? 🙂

Sep 25, 2014 7:58 AM in response to LeeS7237

Calibrated The iphone 5s battery two times.

Deleted facebook.

And phone seems to work fine.


Usage: 30 mins

Stand by: 4 Hours 32 mins.


Apps installed: Instagram, whatsapp


  • Add tracking: off
  • Background app refresh: off
  • Reduce Motion: On
    Track Me(Safari): Off
  • Location: off


P.S. Try Calibrating your phones battery for twice or thrice. And I hope you guys will be good to go..!

Sep 25, 2014 6:23 PM in response to nimishfromlucknow

Thanks for the suggestion! I just upgraded to 8.0.2 (I skipped the 8.0.1 in case of any side affects and bugs), I will see how my battery is, and if there is anything bad, I will follow your suggestions! I have thought many times to delete Facebook but I kind of need it to effectively manage my page on there. There are certain share options that are on FB app but not on mobile FB 😟 Such as sharing to my page through my account looking at my personal account's feed. If there was, I'd do away with my stupid FB app. It's such a huge battery drainer even when background is off and loc-ser is off >_<...

Sep 26, 2014 6:06 AM in response to Crucifixianboss

I never suffered from the heat issue, but I did the battery issue, and I say update it! I haven't hit any problems yet!


I unplugged my phone at 100% at around 12/1 and I woke up at 7AM EST with 100% Now, it is 9:04AM, and I returned a few texts and made a call, and now I am at school with 89%. I wouldn't say it is too accurate since my phone HAS been on standby since 12AM, and so it's at 9HRS, 14 MIN of standby with 50minutes of usage. I'd say this is an improvement if I were comparing to iOS 8.0.0, but probably not the same (still) as 7.1.2, that's my take on it though... Anyone else?

Sep 26, 2014 6:53 AM in response to Sonnto

I did the 8.0.2 update last night. I closed all app except for Lirum so I can monitor the CPU's. I still have the heat and high CPU issues. My CPU's are hovering around 80% (combined).


I'm still under AppleCare (iPhone 5) so I need to determine my next step: take it back to Apple and swap for a different (refurb) unit or do a clean iOS 8 install. Each of those has its own ups and downs so I'll figure out what to do tonight. I made an Apple Genius Bar appointment for Saturday morning, just in case.

Sep 26, 2014 6:31 PM in response to fbara

I did a compete reinstall of iOS 8, my apps, and then the 8.0.2 upgrade. It's been several hours now and my CPU is still hovering between 80-100% on a consistent basis. I posted a picture of my CPUs.


Apple stopped signing iOS 7.1.1 so you can't install it even if you have a copy of it. It looks like I'll be forced to have this iPhone replaced.

User uploaded file

Sep 27, 2014 7:40 PM in response to fbara

I Upgraded to 8.0.2 too. Still with heating and battery issues. I noticed that the CPU clock was running at 1.888 MHz for a while, this is well above the CPU maximum clock informed by Lirum Info. Most of the time it runs at around 400 MHz, even when the CPUs are 60% bussy.


So the cpu's not only adjust the amount of work they can handle, but also the speed of the clock can be incremented when the load of tasks go up and needs extra processing power to crunch more bits per second.


Why I have seen the cpu clock running at 1.88 GHz, when the maximum cpu clock should be 1.4 GHz?


would be this overclocking of the cpu abnormal and started with the iOS 8 upgrade?

Sep 29, 2014 1:08 AM in response to LeeS7237

at this point i must say am really not feeling great anymore,my phone hangs all the time,restarts applications and closes them when ever it wishes,still hot and battery hasnt improved either,having serious propblems connecting to wifi,now i wished i didnt even upgrade to 8.0.2 cause its more of a mess than 8.0 to me.just had to drop the phone at home and go to work cause its annoying hanging all the time

Sep 29, 2014 10:57 AM in response to Pablo Poch

It seems I did a mislecture when I said cpu clock was running at 1.88 GHz (it was 1.88 MHz instead), It was a miscalculation of Lirum info when having too few data to calculate it accurately. After some seconds It was actually running at just below 400 MHz.

In my case I haven't experienced app crashes, or system hang. My problem still remains associated to high cpu usage (around 60%) while doing nothing. Sometimes it slows down to 8-10% and after some minutes of not using the phone you can feel it has cooled down to normal.


As it is known that de location services (GPS activity) eats lots of energy from the battery, I looked then which services were accessing Always location and I turned them to Never all but the necessary apps like Maps, Google Maps, Waze, etc.


I'll see what happens with battery usage now and get back to this thread soon.


I understand that iOS testing had its limitations in field but only in relation to the new iPhone 6 and 6 Plus, due to the restricted testing by few in Apple organization to keep the secrecy of the details of the new hardware until launched to market. In the case of testing on the iPhone 5S there is no limitation on testing because there is no secrecy on the hardware after a year on the market. So it seems to me that the problem is may be related to the better management of energy on the A8 chip compared to the 5S's A7 and also may be because iOS 8 was planned with iPhone 6 in mind. Or iOS 8 should be aware of the harware it is intalled on and adjust itself to it to run the cpu's at proper levels to avoid overheating and overdraining the battery?

Sep 30, 2014 3:49 AM in response to Pablo Poch

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.

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

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