With the excitement generated by the recent announcement of TRAPPIST-1 with the largest group of potentially inhabitable planets, a lot of people would like to learn more about exoplanets. NASA has a great way to do that, with the Eyes on Exoplanets app. Download and install it, and it will generate a scientifically accurate 3D universe populated by more than a thousand planets NASA has discovered orbiting other stars. Just watching the way the stars change as you go from one planet to another is hypnotic. The app has three modules, besides the Exoplanets database/media center it also includes Eyes on the Earth and Eyes on the Solar System, also very fun and educational programs. Since they are all available for free, you might as well get the entire set.