Intelligent RF Signal Detector

Here is another handheld tool that lets you detect audio and video bugs hidden in your property. It comes with a LED proximity display to show you where those bugs are hidden. The device also comes with 8 ultra-bright lens. The Intelligent RF Signal Detector has a wide frequency range and can detect RF, WiFi, GSM, CAM, LTE, 4G, 3G, and other bugs.

The device can be used to detect idle phones too. You can find out more about it here.