I am currently having a Facebook app which is already deployed in the production. Since, Facebook is going to remove the feature "Post to friend's wall" soon. So that, I have to submit the Open Graph action to Facebook to use Mention Tagging instead.
In the submission period, I have to deploy the new website and wait Facebook to review it.
The problem is:
During the time that I am waiting Facebook to approve the action, other users in my website will not be allowed to use mention tagging.
Since the site URL of Facebook App can be only one (which is now pointing to production). So I couldn't deploy the testing stage to another URL and point the site URL to it.
What should I do? Thanks.
Set the App-Domain to "yourapp.com".
Now have the regular, live app at www.yourapp.com or whatever, and put the new version, which is to be approved, at beta.yourapp.com. When submitting the action, point to the beta.yourapp.com-URL - the platform-team will follow your links.
The bottom line: setting the App-Domain allows you to run the app on a domain wildcard, *.yourapp.com.