As a device that uses the public airwaves, cellphone signals can be picked up and recorded by anyone with hardware that allows it, and the hardware can be made at home with common components. Law enforcement has been using Stingray devices to intercept and listen to and record conversations for several years now and can do so without a warrant because the phones use public airwaves that by law are open for anyone to use. What is less publicized is that the phones firmware can be flashed making the phone a listening device that can be used even when the phone is not in use. A virtual wire that can be placed on any suspect that uses a cell phone. Now with a little bit of ingenuity anyone with knowledge of how a cell tower operates can make one of the devices themselves at home with parts that are readily available online or at a local electronics shop. The new motto for cell phones is: never leave home with it. And you were worried about Microsoft collecting data about how you use their products?