Ok, now I see the problem the author is trying to solve. Thanks for clearing that up.
I think from an HTTP perspective, the right way to solve this is to use vendor specific content types and have the OS resolve whether to open it in an app or not.
So when a link is clicked on in a browser, you use the request's Accept header to indicate which apps are installed on the device (and have registered a custom content-type). The server then can respond with a custom content type and let the OS dispatch the response to the appropriate app.
For app to app links, the OS could just perform an HTTP HEAD to see which app to dispatch to.
I think from an HTTP perspective, the right way to solve this is to use vendor specific content types and have the OS resolve whether to open it in an app or not.
So when a link is clicked on in a browser, you use the request's Accept header to indicate which apps are installed on the device (and have registered a custom content-type). The server then can respond with a custom content type and let the OS dispatch the response to the appropriate app.
For app to app links, the OS could just perform an HTTP HEAD to see which app to dispatch to.