Slow performance and lag after iOS 26 update on iPhone

...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.

Viinturuth wrote: "My phone still lags and has become noticeably slower since the update"

Viinturuth ~ What model of iPhone is it?...

Settings > General > About > Model Name

And what point version of iOS 26 is it running?...

Settings > General > About > iOS Version

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This works because after updating an app, your phone closes it and makes you reopen it.

A more general fix is therefore to close all apps once after updating. Afterwards you can continue using your phone as normal.

For more details you can check out my full solution here.

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.

Apple support and senior advisors have even noticed the issues themselves. And considering the amount of people that are reporting the issues after this update solidified it as the root cause.

Soloved lag by;

1. Reduced transparenty on
2. Battery save mode off
3. Adaptive battery on

Now 100% smooth

Turning off Apple Intelligence almost solved the issue for me on iPhone 17 Pro max

updated last Friday, the battery life is improving slightly, but the lag is unbearable, when you open an app or swipe up to go to home screen, it takes almost a second for the action to perform. Also the phone is overheating from normal use. It seems by the comments that its a common issue for all models bellow 15 ... I turned down transparency and turned off background refresh and it helped a little with the battery life, but THE LAG is the big problems here. I have never seen anything like that on a iPhone and i use it since model 6.

Same problem here. Lagging a lot and now deleting an app also takes full 5 - 10 seconds. Nothing of that before the update. Every time I switch screens the apps are displaying slowly one after another. Apple ! Please fix this. I contacted them and they said to wait 72hours after the update as the update requires time to update. It’s been 48 hours still same problem. Will wait the full 72 hours and see.

Since 26.0 my iPhone is lagging badly and I keep getting “message failed to send” errors, even though the messages do go through. Apple says it’s not the update, but too many people are reporting the same issues for that to be coincidence. These problems didn’t exist before 26.0.

Updates should fix bugs, not create them, and users should have the choice to disable features that drag performance down. Right now, it feels like we’re being forced into updates that slow our phones and eat storage, with no real help in return.

Nobody here cares if you purchase a Samsung Ultra today. Those nonsensical comments are not going to get an answer to any issue or get the attention of Apple. It just means you have spent no time over at the Samsung support site where you see those same kind of comments saying they are going to buy an iPhone. You have a couple of options:

• Post the screenshot of Settings > Battery that shows the green battery graph with the last 24 hour option and the top apps consuming the battery. In addition, let us know when you updated.
• Wait for iOS 26.0.1 that is currently in beta. We cannot comment on the issues that have been resolved as it is a violation of the user agreement for testing and not allowed on this Support Site.

I have the same problem today after updating my iPad A16 from iPadOS 18 to 26.

In my case (iPad A16 & iPadOS 26), that's enough for fixing. I tested with 3D game Critical Strike, lag issue has gone.

But if the problem is still not resolved, try again after a few days to let the OS finish processing background tasks.

Good luck

https://www.youtube.com/watch?v=k6zwVuDJ9cw

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