iOS 9 Low Power Mode Cuts Performance by 40 Percent
You can't have it all. And by that, we mean that it's often difficult to reconcile lots of battery life against a device's performance. That's the exact trade-off some iPhone users will have to make once they're given the option to put their devices into a Low Power Mode—a tweak that will arrive with iOS 9 this fall.
According to reports, the Low Power Mode works by cutting an iPhone's performance in an effort to preserve battery life. And the cuts work; according to MacRumors, an iPhone can boost its battery life by around three hours when it slashes speed.
The performance difference is about a 40 percent loss. That sounds like a lot on paper, but it might not matter to those who are just using their devices to read email or casually browse the Web. If you're a mobile gamer, you might be a little less thrilled. We have yet to see the Low Power Mode tested on real-world apps, so it's unclear just what that kind of a hit would translate to for today's top titles.
On the Geekbench 3 benchmark, which was recently updated for iOS 9, an iPhone 6 Plus hit a score of 1606 on the benchmark's single-core processor test and 2891 on its multi-core processor test (without any mode or anything applied to the device). According to MacRumors, flipping the iPhone into Low Power Mode dropped its scores to 1019 and 1751, respectively. It got the same performance on an iPhone 5s as well.
That said, flipping an iPhone into Low Power Mode—which will also happen automatically once your device reaches either 10 or 20 percent battery life—can affect your device in other ways, too.
"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," reads Apple's description from the recently released second round of the iOS 9 beta. (No functions changed between the first and second betas; Apple just adjusted its wording for the mode.)
Other tweaks arriving with iOS 9 are also expected to extend iPhone battery life by around an hour or so.
