iPhone 6s Running Slow After iOS 11 Update? Here’s How to Fix It

If your iPhone 6s started feeling sluggish after installing iOS 11, you’re not alone. A major update like iOS 11 can temporarily slow down devices while everything settles in, but sometimes the lag doesn’t go away on its own. Here’s a full list of things you can try to get your iPhone running smoothly again.

1. Reboot Your iPhone (Soft Reset)

Sometimes all your iPhone needs is a few reboots to finish processing the new update.

Press and hold the Power button until you see “slide to power off.”
Slide to turn off your iPhone completely.
Wait about 30 seconds.
Press and hold the Power button again until you see the Apple logo.

If it’s still laggy after one reboot, don’t be shy — restart it a couple more times.

2. Close All Background Apps

Too many apps running in the background can drag your system down.

Double-press the Home button to open the app switcher.
Swipe up on each app to close them.
Press the Home button to return to your main screen.

After closing them out, reboot again to give your memory a fresh start.

3. Update Your Apps

Old, outdated apps can cause slowdowns if they’re not optimized for the new iOS.

Open the App Store.
Tap your profile icon at the top.
Hit Update All or individually update apps.

Once you’ve updated your apps, restart your iPhone.

4. Free Up Storage Space

iPhones need breathing room. If you’re running low on space, performance will suffer.

Go to Settings > General > iPhone Storage.
Check how much free space you have.
Delete any apps, videos, or photos you don’t need.

Aim to have at least 1GB of free space for smooth performance.

5. Check for a New iOS Update

Sometimes a quick bug fix update comes out after a major iOS release.

Head to Settings > General > Software Update.
Download and install any available updates.

When iOS 11 came out, follow-up updates like 11.2.5 fixed major performance bugs — so you don’t want to miss those.

6. Clear Safari Cache

If browsing feels especially slow, clearing Safari’s cache can help.

Go to Settings > Safari > Clear History and Website Data.
Confirm the action.

This clears out junk but keeps things like your AutoFill info intact.

7. Turn Off Automatic Downloads

Automatic downloads can suck up system resources without you even noticing.

Go to Settings > App Store.
Toggle off Automatic Downloads for Music, Apps, and Updates.

This stops your iPhone from trying to update everything at once in the background.

8. Disable Background App Refresh

Another hidden battery and performance killer is Background App Refresh.

Open Settings > General > Background App Refresh.
Either turn it off completely or selectively disable it for non-essential apps.

Fewer apps refreshing means less strain on your iPhone.

9. Reset Your iPhone (As a Last Resort)

If nothing else works, a full reset can wipe out stubborn issues.

Go to Settings > General > Reset > Erase All Content and Settings.
Enter your passcode and confirm.

Tip: Back up your data first! You’ll be setting your iPhone up like new afterward.

10. Still Slow? Contact Apple Support

If you’ve tried everything and your iPhone 6s is still crawling, it’s time to get help. Contact Apple Support or visit an Apple Store to see if a hardware issue (like battery health) could be causing the slowdown.