Users mark their starting point and destination, and the app will trace the great circle arc between the two points (kind of like the live flight trackers some carriers have as part of their in-flight entertainment system). The app then gathers information from Wikipedia and scientific databases to highlight geological points of interest such as lakes, mountains, glaciers, and fossil locations. Users can download the info before they board the plane, and read mid-flight. The app even tracks the phone’s location in real-time using its GPS system so users can see what points of interest are right underneath them. Loeffler adds that the app can be used during hikes and road trips, as well.