A "metal detector" is useful for finding lost accessories or removing hazardous materials, but few people bother to have one at home.
The "Magnetometer Metal Detector App" is useful in such cases.
The Magnetometer Metal Detector App uses a built-in magnetic sensor to measure the surrounding magnetic field.
When you bring it close to surrounding metal (iron, steel) or electronic products, the magnetic field measurement increases, helping you find lost items.
However, gold, silver, and copper coins are classified as non-ferrous metals and cannot be found because they do not have a magnetic field.
The level of the natural magnetic field (EMF) is about 49μT (microtesla) or 490mG (milligauss: 1μT = 10mG).
The accuracy depends on the quality of the magnetic sensor of the installed Android device.