Link harvest: You Can Stalk For As Low As $1000

A study by researchers from the University of Washington shows that for a mere $1000, you can use any of the existing mobile advertising platforms to determine someone's precise location and follow them around. How could that end badly?
https://www.wired.com/story/track-location-with-mobile-ads-1000-dollars-study/?mbid=nl_101817_daily_list1_p1 ;