[Article updated December 7, 2021]
In this video, John McAfee explains how anyone with a device called a “Stingray” can listen to all cell phone calls that are made within a quarter of a mile of where the device is located.
I posted this video a few years ago, but YouTube took it down. I’m very concerned about talking on cell phones, and it hated it when I had to enter information such as account numbers on the keypad. Supposedly your conversations cannot be listened to using that device if you are using an encrypted VOIP app on your phone, however. Such an app can also allow you to converse over your home internet connection rather than over the air as well.
(Note that John McAfee was recently killed in prison after he was arrested on tax evasion charges.)