HOW COPS CAN SECRETLY TRACK YOUR PHONE

"Both the DEA and the Marshals possess airplanes outfitted with so-called stingrays or dirtboxes: powerful technologies capable of tracking mobile phones or, depending on how they’re configured, collecting data and communications from mobile phones in bulk."

If you have to transmit in the clear, use an encrypted protocol.

https://theintercept.com/2020/07/31/protests-surveillance-stingrays-dirtboxes-phone-tracking/?utm_medium=email&utm_source=The%20Intercept%20Newsletter