How to tell if Apple is slowing down your iPhone — and how to fix it

Apple Admits To Slowing Phones Down As Their Batteries Age

Apple recently admitted to slowing down its iOS operating system (or performance throttling) as they get older and the batteries deteriorate, angering customers who say the company is only trying to trick users into purchasing newer iPhone models.

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In a statement to The Verge, Apple said:

“Our goal is to deliver the best experience for customers, which includes overall performance and prolonging the life of their devices. Lithium-ion batteries become less capable of supplying peak current demands when in cold conditions, have a low battery charge or as they age over time, which can result in the device unexpectedly shutting down to protect its electronic components.

“Last year we released a feature for iPhone 6, iPhone 6s and iPhone SE to smooth out the instantaneous peaks only when needed to prevent the device from unexpectedly shutting down during these conditions. We’ve now extended that feature to iPhone 7 with iOS 11.2, and plan to add support for other products in the future.”

But the larger issue among critics isn’t that Apple is slowing down older iPhone models to promote system performance, but that the company didn’t tell customers they were doing so.

This week, Apple announced it would replace iPhone 6, 6S, SE or 7 batteries for just $29. Regular battery replacement costs $79.

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Here's how to tell if Apple is slowing down your iPhone:

1. Affected models

If you have an iPhone 6, iPhone 6S, iPhone SE, your iOS was likely affected with the iOS 10.2.1 update.

For iPhone 7 users, changes came with the iOS 11.2 update.

To check which version of iOS you’re currently running, go to Settings --> General --> About.

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2. Check your battery health

The more you use your batteries, the less effective they’ll become.

To figure out how your battery health is, download the app Battery Life Doctor from the App Store. Once you've downloaded it, go to the details on "Battery Life," which will tell you details about your battery performance.

If you see your device has poor battery health, your phone is highly likely to be affected by the iOS changes.

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3. Check the speed of your iPhone's main chip

Download one of the many apps that gives you information about the speed of you phone's main chip and internal activity. The app Lirum Device Info Lite is one option, according to Business Insider.

Inside the app, tap the options button on the top left --> This Device --> CPU --> and check the CPU Actual Clock against the CPU Maximum Clock.

If both numbers are the same, your iPhone isn’t affected by Apple’s changes.

Another app you can use is Geekbench 4.

For reference, here are the original "clock speeds" — the measure of speed for a processor chip — for these models, Business Insider reported:

iPhone 6 and 6 Plus: 1.4 GHz

iPhone 6S and 6S Plus: 1.84 GHz

iPhone SE: 1.84 GHz

iPhone 7 and 7 Plus: 2.34 GHz

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What to do if your iPhone is slowing down:

- Back up your data.

- Eliminate other reasons your iPhone may be slowing down by updating to the latest iOS system and update all your apps. Check storage recommendations at Settings --> General --> iPhone Storage to free up memory. Turning off app background refresh and location services may also help speed up your device.

- Use the low power mode.

- Do a clean iOS installation.

- Use the Geekbench app or another speed-testing app. If scores are standard, you are likely affected by Apple’s iOS backup.

- Check your battery status using the Lirum app or another battery-testing app. If your phone is affected by Apple’s iOS changes, take the device to the Apple Store.

- Replace your iPhone battery for $29 at the Apple Store if you have an  iPhone 6, 6s, SE or 7, a discounted rate from its typical $79. Even if you plan to upgrade to a different iPhone, replacing the battery will be helpful if you choose to resell the device.

More information at support.apple.com.