A rather sobering article from The New York Times:
The data reviewed by Times Opinion didn’t come from a telecom or giant tech company, nor did it come from a governmental surveillance operation. It originated from a location data company, one of dozens quietly collecting precise movements using software slipped onto mobile phone apps. You’ve probably never heard of most of the companies — and yet to anyone who has access to this data, your life is an open book. They can see the places you go every moment of the day, whom you meet with or spend the night with, where you pray, whether you visit a methadone clinic, a psychiatrist’s office or a massage parlor.
If you’re interested in the apps that are tracking your location, this Twitter thread may be of interest.