New: document we obtained confirms that the Secret Service bought "Locate X," a product that gives the agency access to location data generated by ordinary apps installed on peoples' smartphones. Don't need a warrant as agency simply buys the data instead https://www.vice.com/en_us/article/jgxk3g/secret-service-phone-location-data-babel-street

Law enforcement agencies buying information, and in particular location data, has quickly become a widespread issue. ICE, CBP, IRS, Secret Service. Senator Wyden planning legislation that means authorities can't buy data they usually would need warrant for https://www.vice.com/en_us/article/jgxk3g/secret-service-phone-location-data-babel-street

Here is the document itself https://www.documentcloud.org/documents/7038175-Babel-Street-Secret-Service-Contract.html

And here is the section of the Secret Service contract mentioning Locate X, which gives the agency access to location data gathered by ordinary smartphone apps installed on peoples' phones https://www.vice.com/en_us/article/jgxk3g/secret-service-phone-location-data-babel-street

Babel Street also offers its open source intelligence surveillance product, which we covered in 2017: https://www.vice.com/en_us/article/gv7g3m/meet-babel-street-the-powerful-social-media-surveillance-used-by-police-secret-service-and-sports-stadiums