[lawtalkinghuman]

Yes, I’ve used it to send photos/videos I’ve taken to friends while outside in places where there are no wifi networks.

[tonyedgecombe]

I wonder if it's different if you have it set to "Contacts only". It may need to connect to iCloud.

[darrenf]

I have mine set to Contacts Only, and regularly use it to move photos between iPhone and iPad when on flights (and indeed other locations) without wifi or cellular.