This easy application. otherwise it requires strong support.
First your phone must have a magnetic field of 80 10: 15 seconds 20
 The Stud Detector uses the compass (magnetometer) sensor on your device to accurately target wall studs by locating metal joists
The use is very simple: launch the application on your smartphone and move it. You can see that the level of the magnetic field is constantly fluctuating
When the app does not work properly it means that your phone's sensors are damaged
 You can see that the level of the magnetic field fluctuates constantly. This application measures the value of the magnetic field using the integrated magnetic sensor
the magnetic field level will fluctuate constantly. That's all!
Note: the magnetic sensor is affected by electronic equipment TVs PCs ...
The magnetic field level (EMF) in nature is about 49? T (micro tesla) or 490mG (milli Gauss); 1 μT = 10 mg.
Ghost hunters also use metal detectors for ghost detection because they claim that ghosts have an influence on magnetic fields