Metal Detector is in the 3rd set of the Smart Tools collection. << Metal Detector apps require a magnetic sensor (magnetometer). If this app does not work properly, please check the specifications of your device. >> This app measures magnetic field with an embedded magnetic sensor. The magnetic field level (EMF) in nature is about 49μT(micro tesla) or 490mG(milli gauss); 1μT = 10mG. When any metal(steel, iron) is near, magnetic field level will increase. Usage is simple: Open the app, and move it around. The magnetic field level will constantly fluctuate. That's it! You can find electrical wires in the walls (like a stud detector) and iron pipes in the ground. A lot of ghost hunters had downloaded this app, and they had experimented as a ghost detector. The accuracy depends entirely on your magnetic sensor (magnetometer). Note that it is affected by electronic equipment (TV, PC, microwave) due to electromagnetic waves. * Main features: - Alarm level - Beep sound - Sound effect on/off - Material design * Pro version added features: - No ads - Compass - Sharing GPS location - Qibla finder, Car locator * Do you want more tools? download [Smart Compass Pro] and [Smart Tools 2] package. For more information, watch YouTube and visit the blog. Thank you. ** Metal detector cannot detect gold, silver and coins made of copper. They are classified as non-ferrous metal that has no magnetic field.