Turn on battery saving mode on iPhone, what do users have to trade off?

When enabled, this mode reduces power consumption by turning off or limiting multiple software and hardware features at once. Photo: Nextpit .

Low Power Mode is not a new feature on the iPhone. Apple announced this mode in 2015 with iOS 9. However, there are still many people complaining about their newly purchased iPhone running abnormally slow. The common point in these cases is that they accidentally or intentionally turned on Low Power Mode without realizing that this feature is slowing down their iPhone.

How does low power mode work?

As the name suggests, Apple created this feature to help extend battery life in situations where users don't have a charger nearby. When activated, Low Power Mode reduces power consumption by turning off or limiting multiple software and hardware features at once.

Normally, iOS will prompt users to enable this mode when the battery drops to 20%. However, you can also manually enable this feature at any time via Settings or Control Center.

The sign that your iPhone is in battery saving mode is very simple: the battery icon in the status bar will turn yellow. Photo: iOS Gadget Hack.

Apple describes the feature as follows: “Low Power Mode reduces the power consumption of your iPhone or iPad when the battery is low. When it is on, your device can go longer before needing a charge, but some features may take longer to update or complete. Also, some tasks won’t work until you turn off low power mode or charge your device to 80% or more.”

You can easily tell when your iPhone is in low power mode by looking at the battery icon in the status bar. If it turns yellow, it means this mode is active.

But specifically, what does Low Power Mode affect on the iPhone? Apple has provided a list on its official website, listing the changes when this mode is enabled. Specifically, it includes turning off or reducing 5G usage; limiting the auto-lock time of the screen to 30 seconds; reducing screen brightness and limiting the refresh rate to 60 Hz; turning off Always-On Display; reducing visual effects; pausing background tasks such as downloading, iCloud syncing, backups, and email updates.

One thing Apple didn't mention in the list above: low power mode severely reduces iPhone performance.

Inside the iPhone, the processor has multiple high-performance cores and low-power cores. In normal use, the iPhone can take advantage of all the cores, prioritizing the high-performance cores when performing heavy tasks like video editing or gaming. But when low power mode is turned on, the system limits the use of the high-performance cores. Instead, it relies primarily on the slower, low-power cores.

Should low power mode be on all the time to save battery?

9to5mac 's GeekBench 6 performance test shows a clear difference when turning on and off low power mode on the iPhone 16 Pro Max with the A18 Pro chip. When this mode is turned off, the device's performance score reaches a very high level. Specifically, the single-core score is 3,341 and the multi-core score is 8,270. But when low power mode is turned on, the scores drop quite a bit. Only 1,384 for single-core and 4,093 for multi-core.

Performance measurement results of the A18 Pro chip on the iPhone 16 Pro Max with the GeekBench 6 application. Photo: 9to5mac .

In other words, your iPhone will only run at about 50 percent of its maximum performance when low power mode is on. This change won’t be as noticeable when doing light tasks like web browsing or texting, but it will be more noticeable when you’re playing games, editing photos, or using heavy apps.

Many tests show that this mode has a clear effect when the iPhone is in standby mode, that is, when the device is not used much. However, when the user uses the device continuously, the battery saving of low power mode is not really large compared to using the iPhone in normal mode.

Therefore, instead of turning on low power mode all the time, users should only activate it when they really need to extend battery life such as when traveling , moving long distances or when they cannot charge immediately.

In addition to the iPhone, Apple also has a low power mode for the iPad, Mac, and Apple Watch with a similar operating principle, according to 9to5mac .