calendar is slow to respond after update to ios 15.1 on iphone XSmax

I went to calendar settings and found that sync is set to all events. Changed it to two weeks. Immediately the slowness issue got resolved.

Here's a temp solution I found until they fix the problem:

If I give permission to the Google Calendar app to read my phone's local calendars, it displays the dates and times absolutely perfectly even if they are incorrect in the iOS Calendar app.

I acknowledge that you may not want to share your calendar with Google but if you're struggling as much as me, it might make for a good temporary solution until this bug is resolved.

I have had the same issue. Based on what others have said here I removed the exchange calendars from my phone and the calendar is now working perfectly. I still have a POP email account and that calendar works fine. I still need those exchange calendars for work so I hope Apple does a new update to fix the issue.

I read it was an issue with Exchange calendars & the solution was to remove the Exchange account. Another solution is to switch to Outlook and use that calendar. Or use the Google Calendar. Maybe Apple is trying to make people stop using their calendar? It doesn’t make sense.

Same here. I’ve checked my calendar account settings and it looks like updating is setting the sync option to all events. After switching to Events two weeks ago the calendar is responding almost like normal.

Read somewhere to delete calendar app and re-download it. This definitely helped with the overlapping meetings when changing days. The list view still staggers and eventually freezes when you go about a week into the future. It’s much better though, but still seems like an issue that was never there until 15.1.

I have the same problems, very laggy and the wrong entries are showing. I tried switching to the agenda view and scrolling was very slow. On switching to the agenda view it took me to April 2020 and when scrolling through to today I noticed all the entries for my work calendar that has lots of entries and recurring daily entries were showing. I have the sync set to only go back 2 weeks so I would assume that any entries older than that shouldn’t be displayed. When I remove my work account in the calendar using the Calendars option at the bottom the performance in the agenda view is fixed and scrolls smoothly.

Maybe the sync period is not being honoured and it is causing more data to be used than necessary. The sync definitely worked because I had to change it earlier this year to check on some older entries. Worth checking Apple?

Well, nope, negativ, the originally problem with iOS 15.1 couldn't be solved by changing this setting to 2 weeks. This is my setting since I use an iPhone back in 2008/9 ... that issue got solved with iOS 15.2. Everything else is a different issue ...

Hi Apple, take this: Installed Google Calendar from Apple App-Store. Problem solved! Apple Calendar-App deleted. Done!

Tedinburgh1 - Apple today released iOS version 15.2. It fixes the problem!

kmoliver24 wrote:

I have same issue on my work iphone SE after 15.1 update. My calendar is so slow and won't respond to touch.

Update to iOS 15.2 and it will be fixed

I have this problem as well on both iPhone 12 & iPad after upgrading to 15.1.1 - that said, I discovered today that it only happens when I'm on WiFi. If I'm on cellular, there's no problem. Not sure why the difference. Doesn't matter what WiFi network I'm on (home/work/public). But I've started to turn off my WiFi on my iPhone when I need to access/view the calendar. Not ideal, but a workaround until Apple can fix this with the next software update.

I updated to 15.1 last night and also made various adjustments to privacy and location services based on an article I’d read. Found this thread today when my calendar was locking up and not adding events. Based on suggestions above I removed and reinstalled calendar. After reinstall I was asked and allow edge allowed calendar to track while in use. So far it seems to be working better after those two changes. I wonder if my problem had to do with adjustments I had made to location services.

I deleted the calendar app (not the calendar accounts) and then re-installed it from the App Store.

So far after one full day it seems to be working again with my two different work exchange accounts and a personal Google calendar. Fingers crossed it is a stable solution.

Thank you to everyone that has posted, especially about possible causes. Caching as a potential cause intrigued me. So as five minute experiment I tried the above.

Only minor annoyance was having to change the default calendar colors to what I used before by clicking on the “i” next to the calendar in “Calendars” at the bottom of the calendar app.

Yes iOS 15.2 fixed the issue, but what a pain!

I think Apple has not done a good job this time:

• No information has been published about the issue (causes and affected devices);
• No workaround has been given;
• No date has been provided for a fix;
• Apple support staff has not been trained nor informed, so customers could not rely on them.

This is really bad for such a company.

I think just two communications from Apple would have been enough to change my opinion:

1. “We are aware of this issue and we are working hard to fix it”;
2. ”We solved the issue, a fix will be released with iOS 15.2 in mid December”.

Regards,

/alex