iOS 9 beta 2 Low Power mode Geekbench CPU performance iPhone screenshot 001

With iOS 9, Apple has brought out a brand new Low Power mode which kicks in when you’re nearly out of juice. It was designed to help extend your iPhone’s battery life, providing up to three hours of additional time before charging.

After using Geekbench’s iPhone application to measure an iPhone 6’s processor performance in Low Power, MacRumors was able to determine that this mode reduces processor performance by about forty percent. As a result, an iPhone 6 in Low Power mode would be roughly on par with an iPhone 5s or iPhone 5 in terms of sheer CPU performance.

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. In Low Power mode, the CPU performance was throttled down to preserve battery life so the same iPhone 6 Plus scored 1019 on the single-core test and 1751 on the multi-core test.

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

The test was conducted using a developer preview version of iOS 9. As Apple continues to refine features ahead of public iOS 9 launch this fall, the way Low Power mode works and affects the CPU performance could change.

Geekbench3, a 99 cents in the App Store, has been updated to work with iOS 9.

iOS 9 puts up a prompt offering to turn Low Power mode on when an iPhone’s battery is at 20 and 10 percent. When Low Power is enabled, the battery icon in the iOS status bar turns yellow. Battery percent is always shown in the status bar in Low Power mode.

iOS 9 beta 2 Settings Low Power mode iPhone screenshot 001

Additionally, iOS 9 now prominently nests your battery options inside a dedicated top-level section in Settings.

Interestingly, Apple’s changed the Settings app’s description of Low Power mode on the recently released iOS 9 beta 2. Curiously enough, the updated text no longer explicitly mentions anything about Low Power mode reducing the performance of your device.

iOS 9 Low Power mode description beta 1 vs beta 2
Image via Dayton Lowell.

In iOS 9 beta 1, the original description read (emphasis mine):

Low Power mode reduces performance and network activity to extend battery life. When this is on, Mail fetch, Background App Refresh, motion effects and animated wallpapers are disabled.

And here’s the new description in iOS 9 beta 2:

Low Power mode temporarily reduces power consumption until you can fully charge your iPhone. When this is on, mail fetch, background app refresh, automatic downloads and some visual effects are reduced or disabled.

Fortunately, Low Power mode is an optional feature so you don’t have to use it if you think the tradeoff of not having the full CPU speed available when running low on juice is not worth it.

iOS 9 also employs other tricks to maximize your iPhone’s battery. For example, the software polls ambient light and proximity sensors to determine when your handset is facedown on a table to prevent the screen from turning on when a notification comes in.

Thanks to these power saving tactics, iOS 9 extend the iPhone’s battery by an hour even when Low Power mode is disabled.

Are you disappointed that Low Power in iOS 9 would degrade your iPhone’s performance?

Source: MacRumors

  • Cameron Nelms

    I’ve been using low power mode even when my phones at 100%. Usually lasts the whole day with around 30-50% left. Haven’t notice any downgrade in performance though!

    • Rayon

      Same here

    • L J

      What iPhone do you have?

      • Cameron Nelms

        iPhone 6

    • Guy

      Real world use you won’t notices a difference. Under the hood your iDevice is just using slower clock speeds to get everyday things done.

    • Nik2407

      iPhone 5 iOS 9 b2, no low power mode used… last much longer than on iOS 8.3

  • Bugs Bunnay

    And it wasn’t a feature from the beginning.

  • That_Fruitarian

    ‘Are you disappointed that Low Power in iOS 9 would degrade your iPhone’s performance?’

    Lol… What?

  • jake kneller

    I’ve seen no lack of proformance out of my iPhone 6plus but this really makes my phone last like two whole days my phone lasted me about a day and a half on iOS 8.1.2 jailbroken but on iOS 9 I get about two days with the same amount of usage every day

  • Blip dude

    Won’t care about performance. The point of Low Power Mode is to preserve battery life. It’s just a case of not being able to have your cake and eat it too. Also, my phones battery is now at 95% capacity and I just found out that Apple won’t replace it unless it’s at 80% or below, and seeing as I’m probably not going to hit that mark by November, this will come in handy.

  • Abhinav Chaudhary

    Relax, get high and get a battery bank

    • rockdude094

      B/c everyone loves to carry their usb cable and a battery bank in their pockets

      • Abhinav Chaudhary

        That’s why you need to get high so it wouldn’t be a problem

  • White Michael Jackson

    I guarantee this probably won’t make a difference.

    • Slifur

      Sadly, the beta testers says the opposite.

    • Anton Zuykov

      “I guarantee this probably”
      Words “guarantee” and “probably” are conflicting words!

  • JulianZH

    my old i5 was not even slow…

    • ibtisam

      hey im using iphone 5…… i want complete detail abt the performance…in ios 9!
      will u plz help me

  • Sleetui

    Finally…something Apple has done right.

    • Anton Zuykov

      If that is the only thing that people complain about, that means automatically that Apple has done quite a number of things right already.

  • Pulkit Maloo

    How can we use this in iOS 8.3? I mean which tweak does the same thing?

    • Anton Zuykov

      you can’t.

  • Happy

    ios 9, i sleep last night with 88% battery and next morining wake up it was just 38% facing this problem daily, ios 9 is killing the battery even after low power mode

    • Anton Zuykov

      That is not iOS, but presents that you use! I have no problem!

  • ClaudieX X

    I gonna use Low power mode all day, if I want to do something power intensive, I’ll switch it off and then switch it on again…

  • sunny manghnani

    U can’t use torch light in low power mode