If you want to follow someone in realtime, you don't need to shell out to shady data-brokers like Securus (which use a marketing company that exploits a privacy law loophole to obtain phone location data).There are a whole constellation of location data resellers who will do business with anyone, regardless of the notional privacy protections they promise the carriers they'll put in place.
Notably, these resellers do business with bail bondsmen and bounty hunters, who can, for a few dollars, locate any phone on the major carriers' networks.
The carriers were mired in scandal over the Securus affair last year, and pledged to clean up their act (T-Mobile CEO John Legere tweeted "I’ve personally evaluated this issue & have pledged that @tmobile will not sell customer location data to shady middlemen"). They have not. more
