there are several open source libraries that use location… like https://github.com/AndrewHartAR/ARKit-CoreLocation

and finally, read TN3164: Debugging the synchronization of NSPersistentCloudKitContainer

then read TN3163: Understanding the synchronization of NSPersistentCloudKitContainer

start with TechNote 3162: Understanding CloudKit Throttles

I suspect that all apps using NSPersistentCloudKitContainer will behave the same way? If this genuinely surprises end-users, then it's on Apple to address, not you.

are you doing anything with core data in background threads?

is the question, you are building a new version of your app and want to load an existing store from an old version, and also enable history, does that work and what are the implications? My suggestion is to build a test app, define a core data schema, run the app, generate and save some test data, quit the app, enable the history bit, and launch again, does the call to load stores fail in some way? and if it succeeds, when you add new data, what does the history show?

also, in case you haven't found this yet… https://developer.apple.com/documentation/technotes/tn3162-understanding-cloudkit-throttles

is your code kicking off 100 CKModifyRecordsOperations simultaneously? yes, assume any CloudKit operation can receive a throttling error and respond as needed

In the "Signing and Capabilities" section of your app target, make sure you add the "Background Modes" capability and enable "Remote notifications" https://developer.apple.com/documentation/swiftdata/syncing-model-data-across-a-persons-devices

fwiw, I'm still getting up to speed on Swift concurrency, but I suspect that NSManagedObject is most definitely not sendable.

you can register for notifications of the player for events such as starting, stopping, pausing, etc. While the music player is playing, you'll want to set up a Timer to periodically update a progress bar. In SwiftUI you can use the TimelineView to periodically update the progress bar. https://developer.apple.com/documentation/swiftui/timelineview

I thought I read somewhere that the action to delete storage is only for the dev environment? If you want to delete your data, you can do that via Settings > [Apple ID] > iCloud > Manage Account Storage > [Your App] > Delete

Totally agree! I wrote a whole essay about it, before Apple deprecated the APIs, pointing out some of the missing elements to make a smooth experience. Now, you just have to allow users to send "share URLs" to each other manually. https://deeje.medium.com/cloudkit-sharing-apple-and-you-900441dbef29

ooh ah, you ask a lot of important questions… Is this an expected behavior from using CloudKit? To some degree, yes, as it is specifically designed for backup and sync, and only incidentally does web. Speed is not a feature. That said, you should definitely be using qualityOfService so the system can optimize results. For instance, you might set it high to retrieve thumbnails, and set it low for background uploads. Is CloudKit even a viable option for this kind of app, or is it not designed for this type of app? I think it is viable, though on the public database you have to give very serious consideration to moderation, as well as the limits on public space as it related to the number of users of the app. What alternative approaches could be taken? (Eg. store assets in AWS...) you could go with another cloud service, but then you'd have to consider the costs. Also, regardless of your backend, think thru how to handle large uploads and downloads in the background. For CloudKit, this means leveraging long-lived operations. See CloudCore for an example https://github.com/deeje/CloudCore/blob/master/Source/Classes/Caching/CloudCoreCacheManager.swift