iPhone 13 slowed significantly after upgrade to iOS 27

iphone 13 slowed significantly after upgrade to iOS 27

Posted on Oct 10, 2026 8:19 AM

5 replies

lobsterghost1

Level 10 (233,174 points)

Oct 10, 2026 8:35 AM in response to alpesh146

In addition to what Lawrence Finch suggested, is the battery in your iPhone the original battery which came with the phone when new? At this point, you could have a 5+ year old iPhone. And if the battery is original, it is sure to be failing at this point. What is the Battery Health on your iPhone as shown in Settings > Battery > Battery Health? If it is 80% or lower, the battery is failing and needs to be replaced before something goes terribly wrong, like the battery swelling, which could destroy the phone.

If you have a battery issue, you can schedule an appointment to have it replaced by Apple using this link --> Apple Service and Repair for iPhone Battery - Apple Support

Lawrence Finch

Level 10 (244,490 points)

Oct 10, 2026 8:28 AM in response to alpesh146

Perhaps a long shot:

Do you have a 3rd party VPN installed, even if you are not using it? If so, delete the VPN profile in Settings/General/VPN & Device Management/VPN, then restart your device. Don't just turn it off; delete the profile. Updates sometimes "break" VPN, and it needs to be removed. If that fixes it, you can try reinstalling VPN, but probably shouldn't.

alpesh146 Author

Level 1 (4 points)

Oct 10, 2026 8:48 AM in response to lobsterghost1

Batter health is 77%.

lobsterghost1

Level 10 (233,174 points)

Oct 10, 2026 8:55 AM in response to alpesh146

alpesh146 wrote:

Batter health is 77%.

Your battery is failing and this isn't a when you get around to it problem. Either schedule a battery replacement at your Apple Store as soon as you can or plan to trade the phone in and get a new iPhone.

alpesh146 Author

Level 1 (4 points)

Oct 10, 2026 8:50 AM in response to Lawrence Finch

Checked. No VPN installed

Originally posted at discussions.apple.com/thread/256373732