The Magnetic Sensor app is a useful tool for measuring magnetic fields. It allows you to detect any metal in the environment. If there is any metal in your surroundings, the app will detect it and you will be able to see the value in micro tesla (uT). 

You can use the app as a detector for measuring magnetic fields and for research purposes. For example, you can use it to detect any metal that you might find in the environment, such as in the soil or the air. You can also use it to detect any metal that is in your body, such as in your blood or in your bones.