Why does iCloud Drive change the modified date when I just look at files?

Files stored on iCloud Drive, like many other cloud storage services, often have multiple dates associated with them: I am not clear which date are you referring to.

1. Creation Date: This is the date when the file was originally created.
2. Modification Date: This date reflects the last time the file was modified. It changes whenever the file content is edited, saved, or updated.
3. Opened Date: Some systems might track the date when a file was last opened or accessed. This isn't as common as creation and modification dates, and it might not be visible or tracked for all file types or storage systems.

These dates can be helpful for users to keep track of when files were created, updated, or accessed. They're particularly useful for version control and organizing files based on their activity or relevance.

Yeah, I'm seeing this too (iOS 17.1). It's weird as it doesn't happen on all files, but many of them. I have saved photos from the Photos app to iCloud and when I just view them on iCloud and then close the file, it re-syncs the file and updates the modified date (to the current time).

Sometimes the file size changes too. I've seen a file grow from 688kb to 989kb.

If I view the file 10 times in a row, it will happen 10 times in a row. Very annoying, especially if you care about the modified date.

Update: Perhaps this has been fixed in iOS 17.2 (at least on one file). Still checking.