Slow iPhone? How to Speed Up Your iPhone With 7 Fixes

A slow iPhone often speeds up after three things: a restart, the latest iOS update and a few gigabytes of free storage. If those do not help, check Battery Health, because a worn battery can make Apple limit peak performance on purpose.

That is the short version of how to speed up your iPhone. The fixes below run from the ones that take thirty seconds to the ones that take an evening, so work down the list and stop when the lag is gone. Every menu path comes from Apple's current support pages.

A frozen app or a phone that has been on for weeks

Start with a plain restart. It clears out whatever got stuck in memory and costs you nothing.

On an iPhone with Face ID, Apple's restart instructions are:

1. Press and hold either volume button and the side button until the power off slider appears.
2. Drag the slider, then wait 30 seconds for the phone to turn off.
3. Press and hold the side button until you see the Apple logo.

If the screen will not respond at all, use a force restart instead. Apple's unresponsive iPhone page gives this sequence for Face ID models: press and quickly release volume up, press and quickly release volume down, then press and hold the side button until the Apple logo appears. Apple notes the logo can take longer than 10 seconds to show up, so keep holding.

One habit you can drop: swiping every app closed. Apple says on its app switching page that closing all your apps does not affect overall performance, and an app you quit may not be able to check for new content before you open it again. Only close an app when that specific app has stopped responding.

An old version of iOS

Updates carry bug fixes, and some of those bugs are the kind that cause stutter or battery drain. Apple's update guide lists the steps:

1. Back up the phone to iCloud or a computer.
2. Plug it into power and connect to Wi-Fi.
3. Open Settings, tap General, then tap Software Update.
4. If an update is available, tap Download and Install and follow the prompts.

While you are on that screen, tap Automatic Updates. With Automatically Install turned on, Apple says the iPhone installs updates overnight while it is charging and on Wi-Fi, and you get a notice before it happens. That keeps you from drifting several versions behind without noticing.

Storage that is almost full

A phone packed to the edge has little room to work with, and apps can start hanging or taking longer to open. Check where you stand by opening Settings, tapping General, then tapping iPhone Storage. Apple's storage article explains that this screen shows recommendations plus a list of apps sorted by how much space each one uses.

From there you have three tools:

• Recommendations. Tap Show All, read each suggestion and tap Enable on the ones that make sense. One of them is Offload Unused Apps.
• Offload an app. This removes the app itself but keeps its documents and data, so reinstalling puts you right back where you were.
• Delete an app. This removes the app and everything it stored. Use it for apps you are sure you will not need.

Look hard at the system and AI line items too. Apple Intelligence alone can claim a large chunk of space on recent models, which we covered in how much storage Apple Intelligence takes after iOS 27.

Too much happening in the background

Apps that refresh in the background use processing time and battery even when you are not looking at them. You can trim that in Settings, General, Background App Refresh. Tap Background App Refresh again at the top to turn it off entirely or limit it to Wi-Fi, or leave it on and switch off individual apps that do not need fresh content the moment you open them. A shopping app or a game rarely does. Messaging and navigation apps usually should stay on.

It is also worth knowing what Low Power Mode does, since it changes how the phone feels. According to Apple's Low Power Mode page, it reduces display brightness, turns off some visual effects, pauses iCloud Photos, stops automatic downloads and email fetch, and turns off Background App Refresh. If an app seems slow to show new content, check whether Low Power Mode is on. On iPhone 15 and later it lives under Settings, Battery, Power Mode. On iPhone 14 and earlier it is a switch directly under Settings, Battery. It turns itself off once the battery charges above 80 percent.

A worn battery that triggers performance management

This cause is easy to miss, and it often explains a phone that has slowly gotten sluggish over two or three years.

Open Settings, tap Battery, then tap Battery Health (on iPhone 14 and earlier the item is called Battery Health & Charging). Look at Maximum Capacity and the Peak Performance Capability message.

Apple's battery and performance page explains that when an aging battery cannot deliver enough power, iOS can apply performance management to prevent unexpected shutdowns. The effects Apple lists include longer app launch times, lower frame rates while scrolling, backlight dimming and lower speaker volume. If you see a message saying your battery's health is significantly degraded, the fix is a new battery, not a setting.

For context, Apple says batteries in iPhone 14 models and earlier are designed to keep 80 percent of their original capacity at 500 complete charge cycles under ideal conditions, and iPhone 15 models at 1,000 cycles. If you have AppleCare, Apple's battery replacement page says it will replace the battery at no extra charge once capacity drops below 80 percent.

Apple does let you turn performance management off from the same screen. It switches back on automatically after the next unexpected shutdown, so treat it as a stopgap rather than a cure.

Something that is not supposed to be there

A sudden slowdown paired with pop ups, apps you do not recognize or heavy data use is a different problem. Work through how to remove a virus from iPhone and our signs your phone is hacked check before you spend time on performance tweaks.

Years of clutter that a cleanup cannot reach

When nothing above makes a difference, erasing the phone and setting it up again is the last fix you can do yourself. Back up first. Then go to Settings, General, Transfer or Reset iPhone and tap Erase All Content and Settings. Apple's erase guide warns that this removes everything on the device, including cards in Apple Pay, photos and apps, though content stored in iCloud stays in iCloud.

You can restore from your backup afterward, but if the slowness came from something in that backup, setting the phone up as new and signing in to iCloud is the cleaner test.

When it is time for a repair or a new phone

Book an Apple repair or contact Apple Support if Battery Health reports significant degradation, if the phone shuts down on its own, or if it is still slow after a full erase. Those signs usually point to hardware rather than settings.

If your iPhone no longer gets the current version of iOS, an upgrade may be the honest answer. A good refurbished model can be a sensible middle ground, and our refurbished iPhone checklist covers what to inspect before you buy. You will find more phone guides in our gadgets section.

Before you go that far, give the first three fixes a fair shot. A restart, a current update and some breathing room in storage clear up a lot of everyday lag on their own.