Other Apple is slowing down older iPhones based on battery wear level [MERGED]

IsaacM

macrumors regular
Original poster
Jul 8, 2011
118
91
It has lately been discovered by r/iphone users on reddit that iOS has a secret feature that underclocks your iPhone's processor speed when your phone's battery gets worn out.

People have been noticing their phones becoming really sluggish and slow with time. Previously it was believed it was caused by new versions of iOS, but now it's been discovered that it's actually connected to battery use.

So if you have an iPhone with a battery that has been used quite a bit, there is a big possibility your iPhone has been slowed down in order to keep battery life up.

Here's the original post:

My iPhone 6S has been very slow these past few weeks, and even after updating multiple times, it was still slow. Couldn’t figure out why, but just thought that iOS 11 was still awful to me. Then I used my brother’s iPhone 6 Plus and his was... faster than mine? This is when I knew something was wrong. So, I did some research, and decided to replace my battery. Wear level was somewhere around 20% on my old battery. I did a Geekbench score, and found I was getting 1466 Single and 2512 Multi. This did not change wether I had low power mode on or off. After changing my battery, I did another test to check if it was just a placebo. Nope. 2526 Single and 4456 Multi. From what I can tell, Apple slows down phones when their battery gets too low, so you can still have a full days charge. This also means your phone might be very slow for no discernible reason. Check your Geekbench scores and see what you get if your phone is still slow!

TL;DR Apple slows down phones with low capacity batteries, replacing it makes them full speed again. Check Geekbench Scores.

Imgur Link

Edit: some more information from all of these comments, very informative. Anyway, apparently no one with a 5S has been affected here so far. Not sure why. I also found out a bit more about why this happens. Let me explain: Many people might remember that iPhone 6S battery fiasco, which for many, was fixed with iOS 10.2.1, and that seemed to be the end of it. Apparently, the way it did this is by dynamically changing the maximum clock speed relative to the voltage that the battery is outputting, so that your phone can’t draw too much power and shut down. I also don’t know for certain, but I believe that the iPhone 7 and up are not affected by this nearly as much, since the A10 and A11 chips have separate “low power” cores that apparently run at around 1/5th of the power of the main cores, and will use those as often as possible, and only kick in the fast cores when necessary, meaning you should only see slowdowns for more intensive tasks on the 7 and up, since only one set of cores can be running at once. Geekbench should still let you know though, regardless. Also, some apps might be able to tell you your current clock speed, and if this is true, you can use that instead to find out exactly how much your phone is downclocked, if at all. I will put my old battery back in and verify this when I can.

Edit 2: Some information on replacing the battery: you have 3 options. 1. Go to Apple. They will fix it for you with a 1 year warranty, and you are guaranteed it will work. It is $79 to get a new battery from them. 2. Go to a reputable third party repair shop near you, some examples are Experimac or Batteries + Bulbs, they can do it for $30-40 usually, and under and hour if you come in at the right time. You should get a warranty from these shops if they’re any good. 3. Go on iFixit and do it yourself. Provided you have the right tools, (and you MUST have the right tools) you can do it yourself, for a first time repair, in 30 minutes or less. Be very careful, look up guides, and be prepared. Batteries can be found on Amazon, eBay, or on other specific sites such as MobileDefenders that sell phone parts, usually from $9-20 depending on who you buy it from.

Edit 3: This is not changed when plugging into power, it still results in a slow phone if your battery has a low enough voltage, and therefore your cpu has a lower clock speed.

Edit 4: thank you to u/Adolf-Intel for his comment on CpuDasherX, a free app from the App store that I just used with my old battery to verify it, and it does indeed show a reduced clock speed. Use this to test if your phone has been downclocked, and by how much. you should be able to look up what the original clock speed is for your device and compare it to what the result is in the app. (Scroll down on the default app page and it should be near the top of the screen when scrolled down to the bottom)
There are almost 500 with people confirming this on their own devices: https://www.reddit.com/r/iphone/comments/7inu45/psa_iphone_slow_try_replacing_your_battery/
 

tonybarnaby

macrumors 68020
Dec 3, 2017
2,146
1,498
Seems odd to me that this is just coming out now. I’m not saying I don’t believe it, but wouldn’t someone have discovered this sooner? How many tens of millions of iPhones are out there?
 

IsaacM

macrumors regular
Original poster
Jul 8, 2011
118
91
Seems odd to me that this is just coming out now. I’m not saying I don’t believe it, but wouldn’t someone have discovered this sooner? How many tens of millions of iPhones are out there?
Apparently it's been a "feature" since 10.2.1

There are hundreds of users reporting underclocked processors on their iPhone based on high batter wear level.

While Apple might say they've done this to prolong battery life, it's questionable at best. One could say it's a sneaky way to slow down older devices every 2 years in order to push people into upgrading their iPhones.
[doublepost=1512928173][/doublepost]
So planned obsolete isn’t real ?This is pretty interesting.
It's kind of real.

Considering Apple doesn't notify their users that their iPhones have been significantly slowed down due to batter wear level, most people just assume their phones are too old for the new iOS and go for an upgrade.

If Apple was transparent about this feature, I'm sure more people would replace their batteries and continue using their old device at full speed (which they had when they bought the phone).
 

orev

macrumors 6502
Apr 22, 2015
450
790
Seems odd to me that this is just coming out now. I’m not saying I don’t believe it, but wouldn’t someone have discovered this sooner? How many tens of millions of iPhones are out there?
Now is the time when batteries in those phones would be wearing out, enough to the point that people would notice the slowdown and start to investigate it.
 

eyoungren

macrumors Core
Aug 31, 2011
22,090
14,809
ten-zero-eleven-zero-zero by zero-two
It's kind of real.
Gee.

Good thing my 6s+ has stayed jailbroken on 9.0.2 for the last 2.2 years.
Good thing my 4s tops out at 9.3.5
Good thing I had my iPhone 5 and my daughter's iPhone 5 replaced for the fourth time in May because they are on iOS 10.x

So, if true, another reason for me to continue to hate any iOS above iOS 6.
 

PeLaNo

macrumors regular
Jun 6, 2017
195
84
Apparently it's been a "feature" since 10.2.1

There are hundreds of users reporting underclocked processors on their iPhone based on high batter wear level.

While Apple might say they've done this to prolong battery life, it's questionable at best. One could say it's a sneaky way to slow down older devices every 2 years in order to push people into upgrading their iPhones.
[doublepost=1512928173][/doublepost]

It's kind of real.

Considering Apple doesn't notify their users that their iPhones have been significantly slowed down due to batter wear level, most people just assume their phones are too old for the new iOS and go for an upgrade.

If Apple was transparent about this feature, I'm sure more people would replace their batteries and continue using their old device at full speed (which they had when they bought the phone).
Maybe they just done that with 6s due to its battery problem.
I think they have a good intentions but it’s seems like double edge sword here
[doublepost=1512929258][/doublepost]
So if you replace the battery does it get faster again?
According to that Reddit post.
When you replace your weared battery,your phone isn’t get underclocked anymore.
 

kazmac

macrumors G3
Mar 24, 2010
8,741
6,738
Any place but here or there....
Thanks for posting this, OP. Apple has always been a bit secretive about some things work, so this isn't surprising. Good to know that battery wear is related to the CPU (and ultimately phone) slow downs.
 

BugeyeSTI

macrumors 68040
Aug 19, 2017
3,492
2,430
Arizona
What’s the big deal? If your cars battery was starting to fail, would you wait till you get stranded before you replaced it? If your noticing your phones battery charge isn’t lasting as long or the performance is unusual, all you need is coconut battery or take it to Apple for a battery check. If It’s around 80% capacity, replace it.. My 6S is over two years old and battery capacity is 93%, it performs wonderfully. If it needed a battery, the cost is negligible compared to the stellar performance I’ve had for two+ years.
 

IsaacM

macrumors regular
Original poster
Jul 8, 2011
118
91
What’s the big deal? If your cars battery was starting to fail, would you wait till you get stranded before you replaced it? If your noticing your phones battery charge isn’t lasting as long or the performance is unusual, all you need is coconut battery or take it to Apple for a battery check. If It’s around 80% capacity, replace it.. My 6S is over two years old and battery capacity is 93%, it performs wonderfully. If it needed a battery, the cost is negligible compared to the stellar performance I’ve had for two+ years.
The problem is people weren't in any way notified about this under the hood change.

Many people purchased new phones thinking their phones are simply outdated.
 

Strelok

macrumors 65816
Jun 6, 2017
1,353
1,570
United States
No, this is specific to certain phones. The 6S had that battery problem, so one of the updates slowed down the affected devices to try to mitigate it. Same thing happened with the iPhone 6. I’m almost 100% sure that plus sized phones are not affected at all, neither should 7’s.
 

IsaacM

macrumors regular
Original poster
Jul 8, 2011
118
91
No, this is specific to certain phones. The 6S had that battery problem, so one of the updates slowed down the affected devices to try to mitigate it. Same thing happened with the iPhone 6. I’m almost 100% sure that plus sized phones are not affected at all, neither should 7’s.
People are reporting the same results with their 7 Series.
 

eyoungren

macrumors Core
Aug 31, 2011
22,090
14,809
ten-zero-eleven-zero-zero by zero-two
What’s the big deal?
Most people will replace their car battery. Because they depend on their car to get them where they are going.

But an iDevice? It's easier just to plug it in then it is to make an appointment, go to the store and then wait for the battery to be replaced. You can still use your phone when it's plugged in.

But, if this is true then plugging the phone in because of a bad battery won't correct for the CPU slowdown.

Plugging your car in and driving around is not possible.
 

BugeyeSTI

macrumors 68040
Aug 19, 2017
3,492
2,430
Arizona
The problem is people weren't in any way notified about this under the hood change.

Many people purchased new phones thinking their phones are simply outdated.
I agree most people aren’t tech savvy enough to realize the difference between degraded performance due to a battery on it’s way out or an older device that has had too many iOS updates that it’s hardware can’t handle. My old iPad 3rd gen should of never had iOS 9 installed by me. It crippled it
 

eyoungren

macrumors Core
Aug 31, 2011
22,090
14,809
ten-zero-eleven-zero-zero by zero-two
I agree most people aren’t tech savvy enough to realize the difference between degraded performance due to a battery on it’s way out or an older device that has had too many iOS updates that it’s hardware can’t handle. My old iPad 3rd gen should of never had iOS 9 installed by me. It crippled it
Apple knows it's average user, which is generally not anyone on this forum.

In knowing it's user Apple banks on their lack of knowledge and a lot of times on their intentional ignorance. Most of these users don't want to know anything about how the tech they hold in their hand works. They don't care.

Apple can take advantage of that and often does. But they also can dictate to this type of customer who believes that whatever Apple does or says is nothing to be questioned.

As long as Apple is taking care of them (as they see it) and their privacy Apple is pretty much allowed to do whatever they wish to that customer. These people don't care because they'd rather not think. Thinking involves effort and that's not something they are willing to give to a device whose technology they could care less about.
 

JM

macrumors 65816
Nov 23, 2014
1,000
1,029
https://9to5mac.com/2017/12/10/iphone-6s-slow-down-battery-fix/

So, hopefully this won't turn into a bloodbath....

How does this not prove that Apple has no problem slowing older devices for personal gain?

Objectively: yes, Apple wants to manage the power when the battery gets old.

But does this not give evidence towards the claim that Apple would slow older devices to encourage purchasing of a new one? (Which could be in a way called... GASP!... Planned Obsolescence?)

I'm not saying it's proof that Apple subscribes to Planned Obsolescence; I'm saying that this is pretty good evidence that they are capable of it, and have behaved in a way that would help one believe that they do.

*and please read the whole article. I'm not a wacko tin foil man, so don't treat me like one.
 

Applejuiced

macrumors Westmere
Apr 16, 2008
40,672
6,532
At the iPhone hacks section.
Yes, replacing the battery boosts the CPU back to it's original level.

It's quite sad that users have to discover these things on their own instead of Apple being up front about them in the first place.
So everyone not knowing about it instead of spending $30-50 for a battery they end up spending $700+ for a new iPhone.
Sounds like a very shady business model that makes them billions...
 

cbreze

macrumors 6502a
Nov 26, 2014
689
361
Oregon
Pretty sneaky way for Apple to get the uninformed masses to get a new phone. And way to go Apple for not being forthcoming with this info.
And , if they didn't have this happen people would just be using their phones as usual thinking they maybe should get a new battery or phone(their choice)instead of being mislead into thinking it's new phone time.
This just totally rubs me the wrong way. The new "X" threw me off the iphone to an extent as it is but this confirms my 7 will be my last. When the slowdown comes to my 7 then it's consider it may be new battery time. Thanks for the post OP. A real eye opener.
 

BugeyeSTI

macrumors 68040
Aug 19, 2017
3,492
2,430
Arizona
So everyone not knowing about it instead of spending $30-50 for a battery they end up spending $700+ for a new iPhone.
Sounds like a very shady business model that makes them billions...
I think the right thing for Apple to do would be have a simple popup to tell the user that cpu performance is being reduced due to an issue with the battery and to have it checked. They seem to love popups for everything else, this type of popup would actually be useful and appreciated
 

Applejuiced

macrumors Westmere
Apr 16, 2008
40,672
6,532
At the iPhone hacks section.
Pretty sneaky way for Apple to get the uninformed masses to get a new phone. And way to go Apple for not being forthcoming with this info.
And , if they didn't have this happen people would just be using their phones as usual thinking they maybe should get a new battery or phone(their choice)instead of being mislead into thinking it's new phone time.
This just totally rubs me the wrong way. The new "X" threw me off the iphone to an extent as it is but this confirms my 7 will be my last. When the slowdown comes to my 7 then it's consider it may be new battery time. Thanks for the post OP. A real eye opener.
If this actually can be proven it should be a big lawsuit.
Cause people with devices that the battery degrades over a few years do experience slow downs and bad performance intentionally done by the manufacturer.
Having no idea that if they replace their battery their device will run much better. But if Apple does that and doesn't tell anyone about it in order for people to get frustrated with bad performance and slowdowns to force their hand to buy new iphones.
Then that is very bad IMO.
 
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