Nowadays, it is widely known that localization systems changed our daily routine. A lot of people are using them but, currently, with localization systems, we are mainly referring to outdoor localization and navigation systems based on global positioning system (GPS). Despite outdoor localization being widely used and highly developed, there is still no standard technology for indoor localization purposes. This issue arises because the satellite based signals are largely attenuated when passing through walls and ceilings, leading to a loss of precision. An interesting alternative, for indoor applications, that does not require installing and maintaining costly equipment in the building is the geomagnetic fingerprinting.