Redirect on apple-app-site-association does not break Universal Links

Documentation says that

apple-app-site-association
file needs to be accessible via HTTPS—without any redirects.

However practice shows, that when this file accessible via redirect, Universal Links are working.


Is documentation outdated?

Can we rely on this behaviour?

Replies

Is documentation outdated?

No.

Can we rely on this behaviour?

No.

Redirection is a very common source of problems with universal links. I’m not sure why things are working for you in this case but I strongly recommend that you obey the documented rules.

Share and Enjoy

Quinn “The Eskimo!”
Apple Developer Relations, Developer Technical Support, Core OS/Hardware

let myEmail = "eskimo" + "1" + "@apple.com"

Sorry to bring back to life this thread after 5 years, but is the best reference I could find.

I experience the same:

  • I have the association file hosted at www.domain.com/.well-known/apple-app-site-association (with www)
  • The url domain.com/.well-known/apple-app-site-association (without www) redirects with code 301 to link above
  • My app has in the entitlements the url domain.com (without www), and does NOT have the url www.domain.com (with www)
  • Universal link domain.com/something (without www) works as expected, opening the app

I would expect universal link domain.com/something to not work, following the documentation that says:

Separately, if you’re proxying the subdomain, make sure iOS doesn’t see that as any sort of redirect. Otherwise the apple-app-site-association file won’t be scraped at all (common Universal Link implementation issue).

Would greatly help if Apple could provide some more information about this given the difference in documentation VS implementation.