Sharing i-cloud photos including Meta-datas

Using iCloud Photos ensures that the metadata on all the connected devices is identical. So while keywords entered on a Mac, for instance, doesn't show up on an iPhone, the metadata is still there.

How you export a picture as a file can change the metadata. The Unmodified Original won't have the comments, etc, that are added later. Exports can be told to exclude some metadata. But the information is nonetheless stored in the Photos Library's database.

What is new in iOS27 and macOS Golden Gate is, that we finally can see the keywords as well on our iPhone, not only on the Mac. And we can assign rating stars that also will be shown on the iPhone and the Mac.

Only the titles and subtitles (captions) are still a mess. On the Mac I need the titles, because only the titles can be displayed below the thumbnails, on the iPhone and iPad I need the captions, because only the captions are displayed in the Info for a photo or video.

My brute force solution - I am keeping the titles and captions identical in Photos for Macs, then I can see them on all devices.

The Photos apps in iOS and iPadOS simply do not have as rich a metadata display as on macOS or on the iCloud web version. They provide only the single "Caption" field (versus separate "Title" and "Caption" fields of macOS and iCloud). (Those are the names in US English; they may vary in other language settings.) I am not aware of a "Subtitle" field in US English versions.