For as little as $7,500 a year, Virginia-based Fog Data Science offers a service called Fog Reveal that uses that ad-ID to track a device's wanderings, when location services are enabled.
All mobile devices are assigned what's called an advertising identification number, a unique code that allows apps with location services to target consumers with promotions.
Documents reviewed by The Associated Press show that Fog heavily markets its product to law enforcement. The company promotes what it calls a "pattern of life" analysis, which can stretch back months.
Public records specialist Bennett Cyphers, an advisor with the Electronic Frontier Foundation, calls Fog Reveal "sort of a mass surveillance program on a budget." He and others believe police use of the platform without a warrant is a violation of people's Fourth Amendment rights.
With the U.S. Constitutional right to abortion abolished in June, some U.S. states have criminalized travel that results in pregnancy termination.
Cyphers says "It [Fog Reveal] can be used to run dragnet searches on locations that provide abortions and then work backwards to figure out who the people are who went to a particular facility during a particular time frame."
One fan of Fog Reveal is Arkansas prosecutor Kevin Metcalf. He says Fog simply uses data that people give away for free, and that it is most useful in cases where time is of the essence.
Metcalf, who also leads the National Child Protection Task Force, a nonprofit that combats child exploitation and trafficking, says the application has been invaluable to cracking missing children cases and homicides.
Metcalf is dismissive of those who consider this an invasion of privacy and arguably a violation of the U.S. Constitution's Fourth Amendment, protecting people from unwarranted search and seizure.
"I think the fear that comes out here is, I think it's just blown-up way too much," he said
Davin Hall, Former Police Data Analyst, said "I don't think it should be used by law enforcement. And at the very least, I think people should be aware that it is being used, and that this kind of surveillance is going on."
In a written response to The Associated Press, Fog said it cannot disclose information about its customers. The company said it does not access or have anything to do with personally identifiable information and is leveraging commercially available data.