Resources And Going Further - sparkfun MAG3110 Hook-Up Manual

And, if you put a fridge magnet near the sensor, you will see large spike! Be careful though, the sensor has maximum limits of magnetic field strength it can be
exposed to without damage.

Resources and Going Further

This is a nifty little sensor for orientation, but you may want to go beyond the simple compass that this library allows. You can use an accelerometer in conjunction
with this device to create a tilt-compensated compass. SparkFun has a variety of accelerometers available, including the ADXL345.
To get you started in the right direction, here are a few application notes that go into more detail about this:
Calibration of an eCompass - NXP Application Note
Tilt Compensated Compass w/ Magnetometer and Accelerometer - NXP Applicatio Note
You can also check out my project using this guide and the MAG3110, the Digital Compass.
Notice the electromagnetic interference caused by simply heating up my frozen burrito.
Each spike represents the approach of a fridge magnet
MicroView Digital Compass
OCTOBER 24, 2016
Build a portable digital compass using the SparkFun MicroView and the
MAG3110 Magnetometer Breakout.