GPS Calculator is a Swiss army knife tool for working with GPS coordinates. It allows you to perform a number of geographic and location related calculations including distance and area measurements, co-ordinate conversion and geodesic lines projection (WGS-84 model / surface).

The apps functionality allow for four types of operation:

1. Co-ordinate conversion, from and to Decimal degrees, standard GPS coordinates (degrees and decimal minutes), Degrees-Minutes-Seconds and UTM (Universal Transverse Mercator). These kinds of conversion are useful if you have a set of co-ordinates from another source (e.g. carring out survey work, following a route, finding a geo-cache or reading off a physical map).
      
2. Measure the distance between two places, with the line visualised on a map. The shortest distance will be calculated, which, because of the shape of the earth may not be a straight line (a good way to visualise why planes fly over the Arctic, when travelling between London and Seattle). 
      
3. Measure the area of a specified polygon on a map or aerial view (map data from Bing Maps). For example, this can be used to measure the size of a field or a group of buildings.
      
4. Projection of geodesic lines (i.e. line that accurately reflect the curvature of the earth). This means you can calculate what is a given distance and bearing away from a specified location (e.g. what is 20 miles and 45 degrees north of where you are now). The apps uses reverse geo-coding, powered by Bing, to give you a place name, in addition to calculated co-ordinate. 

GPS Calculator, which has been developed by kitya, can be downloaded for free from the Windows Phone Marketplace. 

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