As there been any talk about CloudKit and offline syncing?
CloudKit and offline sync
How exactly would you sync with the Cloud offline?
CloudKit is a transport mechanism. I see no reason why it would ever change. Use Core Data for data persistance.
I currently have a few apps that use iCloud and Core Data but syncing is not stable. I personally would like ot use CloudKit but without offline syncing it is not appealing for my kind apps.
CloudKit is competing with Azure and they have offline syncing for their product.
The whole point of CloudKit is that you control how and when you access the data. It's a cloud database; it's up to your code when you want to fetch / sync it.
If you need automatic syncing to local storage then that's Core Data with iCloud.
Something to take a look at in regards to this is YapDatabaseCloudKit: https://github.com/yapstudios/YapDatabase/wiki/YapDatabaseCloudKit
It has worked quite well for me and is INCREDIBLY well documented (see the wiki there).
Core Data with iCloud only works for private databases, not shared databases. CloudKit can have shared public databases