Archive: https://archive.today/dGaWx From the post: >>These days, if you’re walking around with a cellphone, you’ve basically fitted an always-on tracking device to your person. That’s even more the case if there happens to be an eavesdropping device in your vicinity. To combat this, the Electronic Frontier Foundation has created Rayhunter as a warning device. Rayhunter is built to detect IMSI catchers, also known as Stingrays in the popular lexicon. These are devices that attempt to capture your phone’s IMSI (international mobile subscriber identity) number by pretending to be real cell towers. Information on these devices is tightly controlled by manufacturers, which largely market them for use by law enforcement and intelligence agencies.