Slow performance and lag after iOS 26 update on iPhone

Two things:

• Let us know when you updated.
• Post the screen shot you see at Settings > Battery, that shows the green battery graph with the last 24 hour option and the top apps using the battery.

For the early adopters who updated last Monday, the indexing has already completed and the reports about battery drain, heat, and lag have dropped significantly.

About Apple software updates - Apple Support

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. If that fixes it, you can try reinstalling VPN, but probably shouldn't.

(VPN isn’t the cause of all problems, but it is responsible for a great many)

Edit: Thought this was going to drop under Userkoozer’s response to toggle reduce transparency.

This should be one the top comments. I had to do this on my 4th Gen iPad. It didn’t completely resolve the issue because there is still a slight stutter when swiping between my list of apps. However, it does help a lot! Can confirm, it helped my iPhone 15 Pro max as well!

Not sure if anyone has seen slowness with the camera app. It seems pretty sluggish swiping between camera to video, etc. even with reduced transparency.

Thanks OP for posting this issue, thought I was going crazy!

THANK You for recommending turning off Apple Intelligence. That was a huge help.

My battery health is 87%

Have a ton of storage

And wanted to see if I could reset to an old version because this new ios being slow was brutal. Turning off the AI helped a ton so far.

THIISSSSS!!!!!! THANK YOU SO MUCH ! I just turned it off completely and now my phone is back to being lightning fast

Following up on my previous comment even after turning off Apple Intelligence my iPhone still experiences lag. I have now reduced transparency and deleted my VPN profile again in

conjunction with turning off AI. My iPhone seems more responsive but only time will tell. Apple need to release a patch. I have only had my iPhone 15 Pro for about two weeks and find that my iPhone 13 responded so much better.

THIS SOLVED IT FOR ME THANK YOUUUU. I was late to update to 26 like did it beginning of this month and have been so disappointed because my phone ran so smoothly before. Turn reduce transparency on!! Saved my phone!

Battery saver mode INTENTIONALLY slows down your iPhone to extend the life of the battery.

For low bandwidth: 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. If that fixes it, you can try reinstalling VPN, but probably shouldn't.

I have updated to every release and other iOS26 versions. Every one of them lags terribly, and is hugely buggy, even weeks after updating.

The ONLY ONLY partial solution is turning off Apple "Intelligence" which fixes most of the bugs, but not all.

What is your Battery Health at Settings > Battery > Battery Health > Maximum Capacity?

Turn off apple intelligence. It worked a dream on my 16 pro max. Back to being zippy and useable even with Proton VPN on.

This was exactly it. The transparency setting is causing functional lag even in higher processing devices. It’s a bug not a feature.

While toggling helped it didn’t eliminate lag in say the search/text pop up but leaving it off does.

you found the culprit.

...i'd like to add one detail I've noticed that I think has to be part of the problem or where the problem partly lies: if my phone is fine, not too many apps open and its having one of its better moments (for the sake of this post lets say that means when its not quite as laggy), and I plug it in to charge, within minutes the battery/phone starts to heat up like never before and then, its slow as a slug... so just sitting there, charging, using just Apple bricks and charge cables, it starts to hear up a lot to the point where I have to unplug it... while in the car, It even gets so hot it gives that "too hot" warning and shuts off... only solution is to unplug it and let it cool off... if it stays plugged in it wont cool off... and please note, this same phone NEVER had that experience before the update...

Along the same lines... once my battery got down to around 7% and I plugged it in to charge up... it heated up, but this time seemed ok, but then I noticed that slowly but surely, the battery drained while it was plugged! It drained to 1% and I left it, no apps on nothing. Came back 30 minutes later and still at 1%...

The only thing that got it to charge up was switch Apple brick to the more powerful Apple brick, the 60W one. Then it charged up quite quickly and smoothly...

So again, I dont know what the new iOS did to create all these issues, but maybe how it handles the Battery is part of the problem, because as many have said, this behavior was non-existent before iOS26...

Rapp_J wrote:

Wrong. It's been way more than 3-5 days. It's been like 2 weeks, and my phone is still lagging significantly.

Did you read the post I replied to? The user updated an hour ago and Apple states clearly that you should be experiencing lag, battery drain, and heat for a couple days as seen in their Support Article. That is what is expected.

For your case, you have not provided any information that would be helpful:

• Did you Reset Settings?
• Have you performed a Factory Reset?
• What is your Battery Health?
• Is this in a specific app?
• Is this while browsing the internet?
• Do you have a VPN installed?

Without any information, you have a couple of choices:

• Schedule an appointment at Apple for diagnostics.
• Wait for the next release of iOS 26.1. It is currently in beta, so we cannot comment on the issues that have been resolved as it is a violation of the terms of use for being a beta tester.

It's horrible. I mean I just bought an iPhone 17 pro and I have never experienced performance this bad on a brand new late model iPhone due to an update. I tested the 15 pro and 17 pro side by side with apple intelligence on and they seemed the same, maybe less heat generation on the 17 pro was noticeable. design choice for IOS 26 is even worse, it gives me a migraine. turning off Apple intelligence seems to help right now but I really hope these issues are addressed as in my perspective, they are causing a really bad user experience.