Slow running iPhone? Here’s the first thing you should check to fix it

iPhone 16 Pro Max shown in hand
(Image credit: Tom's Guide)

Have you noticed that your new iPhone seems to be running a little slower than expected, even after you delete a bunch of files? A recent report from 9to5Mac has revealed the possible reason.

While there are many reasons why an iPhone could slow down, one of the main culprits is surprisingly putting the device in Low Power mode.

Apple's Low Power mode works by limiting several actions in the background, but also changes how the phone utilizes its chip.

Instead of using both the efficiency and performance cores, Low Power mode drastically reduces the iPhone's performance by focusing on efficiency cores to get stuff done.

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Row 0 - Cell 0

Single-Core

Multi-Core

iPhone 16 Pro Max

3532

8733

iPhone 16 Pro Max (Low Power mode)

1387

4232

We ran Geekbench on our iPhone 16 Pro Max, which comes with the A18 Pro chip, to show what this means in terms of actual performance.

As you can see above, Low Power mode cuts the overall processing power nearly in half — drastically reducing the power of the phone. As such, the iPhone 16 Pro Max suddenly has the computing power of a much older phone.

iPhone 16 Pro Max Geekbench scores while on Low Power mode

(Image credit: Future)

When it comes to what this means as a user, essentially the speed at which the phone can complete actions, including loading web pages and fetching data, will be much slower. However, surely you get the benefit of your phone running for longer, right?

The problem with that idea is that, for the most part, Low Power mode isn't really designed to keep your battery from draining while in use. Instead, it's designed to limit the background actions that drain power while the phone is in standby mode. It does have an effect when using the phone, but you'll see diminishing returns on how much power it will actually save.

How to access Low Power mode

(Image: © Future)

Turning Low Power mode on or off is pretty easy to do, all you need to do is head into the Settings menu on your phone.

Once there look for the battery tab and tap it. In the following menu, you'll see the Low Power Mode option as one of the first options.

In reality, Low Power mode is a backup feature rather than something you need to have turned on constantly. Nowadays, the majority of the best iPhones can comfortably run for the entire day with little issue.

However, to keep that kind of capacity you do need to work to maintain your phone's battery health, thankfully we have a full guide to help keep your phone battery healthy.

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Josh Render
Staff Writer

Josh is a staff writer for Tom's Guide and is based in the UK. He has worked for several publications but now works primarily on mobile phones. Outside of phones, he has a passion for video games, novels, and Warhammer. 

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