axiom-icloud-drive-ref

To implement iCloud Drive file sync, use ubiquitous containers to save and read files, coordinate access with NSFileCoordinator, and configure the necessary iCloud entitlements for your iOS and macOS app.

NSFileCoordinator coordinates file access within ubiquitous containers during iCloud Drive synchronization, preventing data races when multiple processes or devices attempt to read and write to the same synced file simultaneously.

Resolve iCloud Drive file conflicts during synchronization using NSFileVersion to detect, manage, and select the correct version of a file when conflicting edits occur across multiple Apple devices.

Yes, you can use NSUbiquitousKeyValueStore to sync small application preferences across Apple devices, providing a lightweight alternative to file-based iCloud Drive synchronization for non-document data.

Check iCloud Drive file download and upload status by inspecting URL resource values, querying the file's metadata to determine if a ubiquitous item is fully downloaded or still pending upload.

Configuring iCloud Drive integration requires enabling the iCloud entitlement and specifying your app's ubiquitous container identifiers in your project's capabilities for iOS, iPadOS, and macOS.