I've seen similar questions on the subject, but haven't seen anything that addresses this directly.
When feeding our URL into the API Validation Tool, in the Link to Application category, we get the following results:
Link to Application
I can't verify that the `apple-app-site-association` file is being requested–our site is such high volume that a single request would be virtually impossible to isolate.
Our app has been in the App Store for well over 48 hours.
Our app identifier and other values are confirmed as correct in the AASA, and there are no issues with redirects, https, or JSON formatting. We have the correct entitlements in the Release configuration of our project in Xcode, in the format of `applinks:www.<domain>.com`.
The behavior we're seeing is that Universal Links are honored on some devices, but not others. Often times, trying to open a link via Slack will open in Slack's own webview. On other devices, this will trigger our app to launch. Opening links via Mail or Notes apps seems to "fix" the issue on affected devices.
I'm curious to know when the AASA file is meant to be requested by the device. When and how often does iOS check that file for updates?
Why does the API Validation Tool mark us as requiring action? What is it running the check against to do its validation? My expectation was that it was checking the App Store for applications that have our domain as part of its entitlements, but we've definitely done that.
Thanks for any and all insights.