iPhone 6 very slow with IOS 11 update

Hi Andrew,

Agree on mjestic's feedback - very informative and useful.

Both of you offered useful, practical information that can enlighten and/or assist many, I feel sure. Ty both for that!

Loving the idea of the battery pack, esp for that price.

I know many who may follow in your lead to help with the performance of their devices. I'm definitely passing that idea forward :)

This worked for my iPhone 6. Resetting to factory settings worked. The other methods did not work for me. The difference is that only resetting to factory settings wipes the phone and does a clean install of the iOS. This indicates that the over the air update (applies ”patches” I think) broke the iOS for some phones.

Here’s what I did:

Backup iPhone 6 to computer using iTunes and encryption.

Restore the phone to factory settings. iTunes will download the newest iOS and may take a while.

Set up as new phone.

Restore from backup.

Do some housekeeping.

Done.

CPU Dasher confirms that CPU running at 1127 MHz after factory reset vs. 600 MHz before reset.

I think that there was more happening than just slower CPU. Non-responsive home button cannot be due to slower CPU.

I hope that this works for you.

Chee-Wui Chu wrote:

CPU Dasher confirms that CPU running at 1127 MHz after factory reset vs. 600 MHz before reset.

I think that there was more happening than just slower CPU. Non-responsive home button cannot be due to slower CPU.

Could you let us know if your phone continues to run at 1127 MHz even when the battery starts to drain.

That is what makes a difference on my iPhone 6. If the battery is fully charged the CPU runs at 1127 MHz. Once the battery drains below a certain level (90% in my case) the CPU slows to 830 MHz and then 600 MHz.

Reset settings most likely deletes the file that hold statistics data about the battery power curve over time. I expect the phone will monitor the battery power output through a few complete battery draining and recreate this file. Then the phone will itself in the low current / low perf mode as before.

*****

<Edited by Host>

Just had a new battery put in my iPhone 6 and it's like a new phone again. I can now open Messages and start typing immediately—no more waiting 15+ seconds for the keyboard to appear and have the first few letters I type missed. And I can open the camera and immediately start shooting—no more waiting 10-15 seconds to be able to take a photo.

Just glad I didn't upgrade my phone, thinking it was because my iPhone 6 was "old".

Apple just confirmed that they are throttling phones that have degraded batteries, to prevent the phones from spontaneously shutting down.

Our goal is to deliver the best experience for customers, which includes overall performance and prolonging the life of their devices. Lithium-ion batteries become less capable of supplying peak current demands when in cold conditions, have a low battery charge or as they age over time, which can result in the device unexpectedly shutting down to protect its electronic components. Last year we released a feature for iPhone 6, iPhone 6s and iPhone SE to smooth out the instantaneous peaks only when needed to prevent the device from unexpectedly shutting down during these conditions. We’ve now extended that feature to iPhone 7 with iOS 11.2, and plan to add support for other products in the future.

There's an article about it at Tech Crunch: https://techcrunch.com/2017/12/20/apple-addresses-why-people-are-saying-their-ip hones-with-older-batteries-are-running-s…and another one at the Verge: Apple confirms iPhones with older batteries will take hits in performance - The Verge

Glad to have an unequivocal statement from Apple. It sounds like they won't be issuing a fix. (This *is* the fix.) Time to replace my batter.

You are right. The CPU dropped to 830 MHz at about 90% battery and then to 600 MHz at 70% battery.

However, the factory reset fixed my other problems. Before reset, CPU was running at 600 MHz at full charge, home button was unresponsive more than once a day and “Hey Siri” was misbehaving. e.g. If I say “Hey Siri, what is the time?” Siri would wake up but would not have heard the time request. It would sit there waiting for me to say something. I just tested Hey Siri by plugging in the power with battery at 60% and it worked. It woke up, parsed the request and responded.

After 24 hrs, those problems have not resurfaced. Yes, the phone is more sluggish when power drops to 70%.

There appears to be several issues. The CPU slow down is probably by design. The others may be due to corrupt OS.

I hope that Apple is investigating and will make an announcement when they figure it out. They have a history of keeping mum until they have a solution. 🏼

I believe what you're seeing is an old battery behaving inconsistently. The throttling happens in response to decreased voltage from the battery. Temperature and other factors can affect that, as well as charge level. It could also be affected by which cells within the battery are holding the charge. Short story: getting a new battery ($80 from Apple) should fix the problem, at least for as long as that battery lasts.

Buzzfeed has an article on this today:

Apple Does Make Your iPhone Slower As Its Battery Gets Older

I checked with a couple apps and I fall into this category - will be going to an Apple Store on Friday to get a replacement battery (iPhone 6, 3 years old). I'll report back.

Hi. Well I've tried everything on this very helpful page, even a complete re-install and restore from backup. Nothing works. IOS 11 slows an iPhone 6 down to a crawl. Appalling. I have now upgraded to an iPhone 8. My problems are solved. It goes like the wind. It seems to be a cunning ploy by Apple to get you to upgrade. Thanks to some clever lads in the EE shop, it has cost me £75 for two new phones, and my monthly bill is £20 less. Result!

Yea just go get an android. the newest version did not fix one thing, in fact my 6+ runs even slower. As i type right now there is at least a 3 second delay from the digitizer to the text appearing on screen. UNACCEPTABLE. This is how they force you to go and buy the newest iphone. sickening business model. steve jobs is rolling in his grave. apple will not fix it. That I can tell you.

mok1987 wrote:

Wrong. My battery isnt old at all, i got this phone last year. It is deliberate cpu throttling with perfectly capable hardware.

Battery age is not a question of months or years but of charge cycles. Depending on how and how much you use a phone, a battery can begin to show age after less than a year or last for two or three or four. Download the app Battery Life and see what it says about the health of your battery. If it indicates that it's failing, contact Apple for a diagnostic.

I still haven't updated to iOS 11 for fear of a slow phone. So when I do, I'll follow all the suggestions here. If its still slow, I'm gonna take the iPhone 6 to Apple and have them deal with it. Whatever the cost, it'll be cheaper than buying a whole new phone.

I still haven't updated to iOS 11 for fear of a slow phone. So when I do, I'll follow all the suggestions here. If its still slow, I'm gonna take the iPhone 6 to Apple and have them deal with it. Whatever the cost, it'll be cheaper than buying a whole new phone.

Download Battery Life and/or CPU DasherX (both are free) and check on your battery condition. If Battery Life says your battery wear is high or very high, get the battery replaced before upgrading. Definitely cheaper than a new phone!

mok1987 wrote:

18% wear on the battery according to the battery life app. So the battery has average wear, not a bad battery. try again apple shill

I fail to see how being rude is necessary. It's certainly not appropriate.