iTopography is an iPhone application developed to compute the area of any surface!! iTopography is available on the appStore and costs 2.39€ or $2.99.
iTopography is developed on the premise that a surface can be approximated as a polygon with finite number of vertices (points). In the case of a strong GPS signal, iTopography uses the GPS device to find the location (longitude and latitude) of the current position. In the case of a weak signal, the user gives the distance between two adjacent points, and iTopography implements an efficient algorithm to compute the location of this points. Once the location of all the points is calculated, iTopography draws the surface and calculates the area and the perimeter.
iTopography runs on OS version 3.1.2 or greater.