CrowdMag is a free tool that uses your smartphone to measure the magnetic field and display the results as a graph or map. You can measure the field in units of nanotesla (nT; one nanotesla equals 10^−9 Tesla).

CrowdMag is a tool for researchers and amateur scientists, and it can be used for various purposes. For instance, you can use it to measure the magnetic field during your outdoor adventures or to conduct your own backyard experiments.

You can also use it to measure the magnetic field of electrical devices and to find out how the earth is being affected by cosmic rays.

If you want to have a better understanding of the Earth’s magnetic field, you can get help from CrowdMag. You can export the data from your device and send it to our server.