Well dang, I've got such an app. My app allows a user to point-and-click on specific points to create a "path" for a UAV to follow. It outputs the coordinates, which can then be programmed into the UAV's controller. It also gets the terrain elevation at each point to ensure the UAV remains above a specified altitude, AGL. Oh well. - http://www.nuclearprojects.com/ins/flightpath.shtml