Please note android gles2.0 devices only with Compass and GPS ( and requires a network connection for map tiles and search).Please follow your devices compass calibration procedure to get best results. Find the Sun/Moon rise and set times of a given time and location, ShadowTrac will use the devices compass and GPS to display in 3D world where the Sun/Moon positions are at currently in 3D, also the positions of the Rise/Set of the moon and Sun are displayed.The App will also show the shadow angle on the map so you can see the effect of the sun angle on the shadows.Features include.*3D Compass.*Scrolling map (or use GPS for location), the maps require an internet connection but they are a visual aid