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With iOS 9, Apple introduced a Low Power mode, designed to extend battery life when an iPhone's power is running low. According to the feature's description, Low Power mode works by reducing an iPhone's performance and cutting down on background activity.

Geekbench 3 has just been updated to work with iOS 9, letting us get a more detailed look at how Low Power mode works and how much it throttles an iPhone's CPU performance when activated.

Without Low Power mode activated, an iPhone 6 Plus scored 1606 on the single-core processor test and 2891 on the multi-core processor test. When Low Power mode was turned on, the same iPhone 6 Plus scored 1019 on the single-core test and 1751 on the multi-core test, suggesting there's a significant performance reduction when Low Power mode is enabled to save as much battery as possible.

lowpowermodeperformancereduction-800x707.jpg

Results were similar on an iPhone 5s, with performance reduced by about 40 percent. We saw single/multi-core scores of 1386/2511 without Low Power mode and scores of 816/1405 with Low Power mode turned on.

Low Power mode activates when an iPhone is at 10 or 20 percent battery level, providing a popup that lets users toggle it on quickly. It can also be turned on via the new Battery section of the Settings app. When it's turned on, in addition to lowering CPU speeds, Low Power mode also disables Mail Fetch, Background App Refresh, motion effects, and animated wallpapers.

Indicated by a yellow battery icon, by limiting performance and disabling battery draining features, Low Power mode can extend an iPhone's battery life by up to three hours. Other performance improvements in iOS 9 extend the iPhone's battery by an hour even when Low Power mode is not enabled.

iOS 9 is currently available to developers and will be released to the general public in the fall.

(Thanks, Brandon!)

Article Link: Benchmarks Show iPhone Performance Difference When iOS 9's Low Power Mode is Activated
Of course the low power mode should work that way! What do you expect?! I don't believe in magic! Like if you want to save food, you gotta eat less.
 
Geekbench 2 was somewhere around 1700 on a top-end water-cooled PowerMac G5. So iOS 9 Low Power mode should be similarly blazing fast on an iPhone 6.
 
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iPhone 7,1 is the iPhone 6 Plus, iPhone 7,2 the iPhone 6. Apple identified the first iPhone as iPhone 1,1.
Seems he didn't notice the difference between comma and period. However I may make the same mistake sometimes. ;)
 
Of course the low power mode should work that way! What do you expect?! I don't believe in magic! Like if you want to save food, you gotta eat less.

It doesn't necessarily have to slow down the processor.

it could have also worked but turning of background app refresh, turned of LTE, lowered navigation calls, turned of automatic brightness and a ton more of other things that has nothing to do with the processor/hard performance of the phone.
 
Who cares. I quit applications when finished and leave Bluetooth and WiFi off when not required. I don't leave everything turn on when not required. It's common sense. People are getting too lazy.

Except this takes it a step further giving you more battery saving than you could have ever done before by throttling the cpu.
 
Who cares. I quit applications when finished and leave Bluetooth and WiFi off when not required. I don't leave everything turn on when not required. It's common sense. People are getting too lazy.
Lazy sometimes comes with convenience, such as washing machine, and public transportations.
All what they need to do is keeping a balance between laziness and convenience.
 
My biggest problem is when there is little or no cellular signal, especially at work. It is a pain to turn airplane mode on/off. It should have a more intelligent method to turn the antenna gain on/off. My phone will drop half the battery level within 4 hours at work. Now I just leave it plugged in the charger and let my Apple watch notify me when I get a message or call as long as I'm within bluetooth range. Unfortunately, I can't connect to the corporate wifi to get more range.
 
My biggest problem is when there is little or no cellular signal, especially at work. It is a pain to turn airplane mode on/off. It should have a more intelligent method to turn the antenna gain on/off. My phone will drop half the battery level within 4 hours at work. Now I just leave it plugged in the charger and let my Apple watch notify me when I get a message or call as long as I'm within bluetooth range. Unfortunately, I can't connect to the corporate wifi to get more range.
Next version of Watch OS should change this thing a little bit, on your watch side.
 
Neat-o.......

I often wonder how much more are "disabled" than just background stuff. 40% is not that bad.
 
That's coming in iOS 10 — the most innovative and magical release of iOS ever.

Sounds about right, since we jailbreakers have had that feature since at least iOS 7*. FlipControlCenter rocks!

* Apple tends to appropriate the best ideas from the jailbreak community (quick reply, anyone?) a couple generations after they appear.
 
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Here is an idea that I think would be great.

How about, in some easy to get to "Settings" area have a slider that allows you to manually adjust the iPhone and iPad's performance, and hence battery life.

Just like you can volume, brightness, even the speed of your car using the foot pedal.

If you are not bothered about speed, why not select to slide the control down the bottom, to perhaps double the battery life of your device?

Sure, of course, we can also have an auto mode....

But why not?

Even if it was say 3 settings, Low, Medium, High it would be something, and if you are going to be away from power for some time, of simply don't want the trouble of worrying about it. Just set it to low.

Sure some things may take a few more seconds to load, or some operations may take 5 seconds rather then 2 seconds to complete, but if the battery lasted twice as long then it may be an option, you, as a user, would be happy to be able to pick.

Would seem a win-win idea.

Phone looks better in the media as battery life gets great life in reviews, and the users benefit form having the option also if they wish to use it.
 
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