A mega-constellation is a collection of man-made satellites orbiting the earth. They operating together to provide internet and other communication services. Because constellations span the entire globe, they have potential to aid society through enhanced connectivity of remote communities and search and rescue capabilities. However, because the satellites reflect sunlight many of them will be visible to the naked eye. The Constellations App simulates the orbits of current and planned mega-constellations. This allows you to explore the effects that these constellations will have on stargazing and astronomy depending on location, time, and date.