Notes App lagging after iOS 18 Update

Your message does hardly make a sense. If you have the sync of notes with the iCloud enabled (>settings, your name, iCloud, Notes<), the notes are regularly synced with the iCloud and therewith obviously are not lost if the app is reinstalled. However, you should bear in mind that the error has still not been fixed - so no change is to be expected from a new installation.

Update iOS 18.1.1 on 13 pro:

The very large note takes about 5 seconds to load once tapped in notes. Typing in the note is slightly laggy most of the time, and sometimes while typing fast I have to slow down to wait for the lag, otherwise it doesn’t register. So, it’s better, but still not the great experience it was. It’s very disappointing, performance the reason I used Apple’s notes vs the competition. It was simple and fast to take a quick note.

Deleting/redownloading and opening/closing app didn’t work. However cutting an entire decently large note and then pasting it back did work. I would imagine the issue may have something to do with mismatches in encoding of old/new notes or something like that. My suggestion would be copy pasting problematic notes into a new note.

Good point. I hoped I had single identifiable notes, but i don’t. The app lags as a whole. However I frequently experience kinda strange behaviour in „newly“ formatted (e.g. folded / unfolded parts) notes as well.

Having the same issue and it's frustrating. I am relying on Apple Notes for work and personal use cases, and ever since Apple Intelligence's latest update it has lagged a lot especially when using collapsable sections. It is ruining the experience for me. It feels like a tiny hammer that is very heavy to lift and use. Apple, please fix this!

This bug is not new. Notes stutters when Typing longer notes since years. But since the last update Typing is near impossible. I don’t know why Apple needs ages to resolve this bug. Special not, because I do send them my user data information…..

This definitely isn't fixed.

I experienced lots of lags on long notes. My notes are primarily only handwritings and some small pictures. The longer the note gets, the more latency and lags I experience. I am already thinking about switching notes app, if this continues

Well, not here. In 18.2, scrolling through the message list seems faster. But that's about it. Everything else, such as the delay when opening a note, the dysfunctional display of search results, the delay when quickly swiping to close a note, is all still there. A really sad performance.

For me it's linked to headings / subheadings, but there are attachments in the notes in question too.

If all of the titles, headings, subheadings are open it scrolls ok, doesn't seem to lag. *** soon as one of them is closed, if I scroll with that closed heading in the view, it lags.

Only happens with big notes, small notes seem unaffected.

Just realised that it’s related to bullet points within a heading for me. If I take the bullet points out it seems to not lag.

Also if I open all the sections and scroll to the bullet points it starts to lag over them, then when they are scrolled out of the view it stops lagging again.

I didn't have any problems before iOS 18 (with thousands of notes) Something went wrong with iOS 18. While I initially suspected faulty iCloud sync, it really seems to ‘only’ affect the app itself (as the app behaves just as ‘laggy’ in flight mode).

Update on my part (1/20/25): The new formatting options that came with iOS 18 seem to be the cause. After a few posts here, I have now made the effort to change all the very long notes I know, which are nevertheless the ones with the new formatting, especially the ‘collapsibility’ of headings and subheadings. 

The app seems to work quite well again. Certainly not as fast as it should be (if, for example, the notes app on an old iPhone 8 with 16 iOS is even faster), but it significantly improves the really very limited usability. 

Perhaps this can help some of you until Apple has the courtesy to fix the issue.

no bugs in ios18 then

Thanks a lot, worked for me and I have 3000 notes, some of them quite large. I never had this issue in my desktop and laptop (mac), just in ios18. Really appreciate your help !