Determining which contacts use Facetime In either the iOS app or the Mac app for Facetime, you are given the option of selecting any contact listed in the corresponding device's Contacts app, regardless of whether they are capable of using Facetime (they own an iPhone or a Mac with the app). Are there any methods of determining this besides manually keeping a register of it or guessing?
To get around this I have added the letters FT to a contacts last name eg "Surname FT"  then all I need to do is search for  "FT" and there I have a list in alphabetical order of all contacts I can FaceTime!

So, create a new message, add all contacts, take note of which ones are blue, and add FT to the end of their surname eg. "Surname FT".  Now when you want to FaceTime someone Type FT into the search bar and presto! You have your list. Hope this is helpful, enjoy :-)