Now that FBML is depricated, does anyone know the best way of returning a list of friends that are also using the same app.
Thanks
From the is-app-user documentation
Please note: We are in the process of deprecating the REST API, and have added
equivalent support to the Graph API for this method. Please use the Graph API
User object and GET /[UID]?fields=installed to check if a user is has TOSed that app.
Also, you already should have the uid of all users of your app, because you have your own state saved, so you could just use that.