FREE App that tracks where light will fall on your land

I'm not sure if the greenhouse forum the right place to put this thread, but after reading the thread that discusses where to put your greenhouse in relation to winter light, I decided to put it here. I am a photographer and light is everything in the photography world. So this is an app called the Photographer's Ephemeris. This is an AWESOME resource for planning your gardens, greenhouses, and I'm sure we can come up with many more applications, because that's just what permies do. If you are looking to buy land, get this first and see throughout the year where your light will be coming from.

http://photoephemeris.com/

"The Photographer’s Ephemeris (TPE) helps you plan outdoor photography shoots in natural light, particularly landscape and urban scenes. It’s a map-centric sun and moon calculator: see how the light will fall on the land, day or night, for any location on earth.
TPE is a universal app with optimized user interfaces for both iPad and iPhone/iPod Touch devices." Yes they have an Android app too!