It would be trivial to determine who has which comped phone.
As soon as it is turned on, geolocation, as soon as the user speaks to it , voice recognition, bounce that against the database, voila.
GOOD INFO! Geo location - and another FReeq suggested Voice Recognition.
Yes, I do believe that it doesn’t matter about knowing how to attach a particular phone to a particular person. Those two things alone can give away the show.