When was the first time that a telephon call was tracked?
According to the Elliot Leiboff post The Beginning of Call Tracking, CallSource® in 1992 was the first and only call tracking company in the U.S.
But I was watching The big sleep 1946 in a scene in 33:27 of the movie when Humphrey Bogart a… Continue reading When was the first time that a telephon call was tracked?