The Stingray is a tracking device. Police say they use it to find missing persons and suspects in violent crimes by honing in on their cell phones. Normally, when a person uses their cell phone the signal goes to the nearest cell phone tower. The Stingray tricks the phone, into sending it's signal to the cell-site simulator and with that police have the user's location. The issue for many is the Stingray doesn't discriminate. It is gobbling up everyone's location information within the device's radius, whether they are part of the investigation, or not. It's not know how big the radius is.