I received a Box link from a contact in the form https://app.box.com/s/[string]/folder/[string]. Clicking this link in iOS Mail app opened a Box web page in Safari with the message "This shared file or folder has been removed." I tried to resolve this by installing the Box app. Clicking the link now opened the Box app with a message telling me I must log in to access my content. This would not be possible for recipients without a Box account.

In macOS Mail, clicking the link opened a Box web page in Safari correctly listing the shared files. Without logging in, I was immediately able to download them.

The desktop behaviour is what my contact would have expected. She was using Box to share files with me as an unknown new contact. The result on mobile looked unprofessional because she seemed to have sent a broken link. If I hadn't checked on desktop, I would have looked unprofessional by replying to this effect, when in fact the link was correct but the behaviour of the Box site and app on mobile was non-functional.

Is this the intended behaviour? Were we doing something wrong? How would we know?