I hope someone can shed some light or point me in the right direction. I have a smartphone that has a Magnetometer built into it. I'm exploring some ideas of how I might be able to use it. I want to be able to detect if two objects are touching each other within a few feet from my Magnetometer. For example, If I have two very small magnets touching each other would that sufficiently alter the magnetic field to be detectable by the Magnetometer in my phone? If I have a magnet and a small piece of metal touching would that be detectable?
Let's say for example that I am close to a door. In the door frame is a magnet and at the edge of the door is another magnet. Could my Magnetometer sense whether or not the door was closed based on the magnets being close to each other?