EarthMeter vs MagVar

With EarthMeter you can calculate distances or areas and their circumferences with an arbitrary number of positions. EarthMeter uses algorithms that take the earth's curvature into account; therefore also far from one another measurement points also lead to correct results. Additionally, EarthMeter is able to calculate and visualize the course between two arbitrary points on earth. All these calculations are based on a user chosen geodetic datum. As measurement units metrical and imperial linear and surface measure units are availble. Another topic that is covered by EarthMeter is the conversion of position coordinates of one coordinate system into another one. For doing so different geodetic datums and projection methods can be chosen from the user. The user has the choice between all commonly used geodetic datums and projections. EarthMeter supports likewise iPods, iPhones and iPads.

MagVar is targeted towards anyone interested in navigation. This includes, pilots of aircraft, captains of sea going vessels, cartographers, engineers and surveyors. Anyone who uses maps and a compass will find the declination calculation (also referred to magnetic variation) very useful. (Declination is the difference between true and magnetic north and used when plotting a course on a map.) MagVar calculates the magnetic flux density for any location on the Earth and then uses this data to calculate magnetic variation. The model is accurate for dates ranging from January 1, 2025 up through December 31, 2029. Using the model, the app calculates declination and inclination. As the user pans the map, the magnetic variation is calculated and graphically shown as a map overlay.