focorner focorner - 1 year ago 123
iOS Question

Should iOS Universal Links work over custom ports?

I am trying to get iOS Universal Links to work for
(i.e. over SSL, but with a custom port number; not the conventional 443 port), but it isn't working.

I'm pretty confident I didn't do anything wrong, since my initial setup worked fine over port 443, and I simply changed the server port to 4443 to test the idea. In fact, I also added support for
in my Xcode project (I tried both with and without the port, without any luck).

I am asking the question, because I couldn't find anything on the subject in the official documentation.

Answer Source

This is expected behavior. There is nothing in the official documentation about supporting non-standard ports because non-standard ports aren't supported.

The only entitlement value allowed by iOS is a valid, bare domain (, which iOS will then use to check for an AASA file over SSL using the standard HTTPS port. In other words, when iOS queries either or, it needs to find your AASA file without any redirects.