My FB app is iOS only at this time. I tried the approach described here Submitting Open Graph Actions for an iOS app? and created a webpage with screenshots to document the user experience.
Facebook has responded by saying I need to show how the app works for the Auth Dialog Preview User. I don't know how to log in to my iOS app with that user. I know it works for canvas apps, does it ever work for native mobile apps?
I've filed this bug in the hope of getting more information: https://developers.facebook.com/bugs/413755695354708
I hope I don't have to build a canvas app as described here Submitting actions for unreleased iOS app? in order to get my action approved.