Have fun learning about sound with this educational app. The San Francisco Exploratorium created the Sound Uncovered app (free) for exploration of acoustic phenomena. Designed like a book, on-screen objects and interactive graphics encourage you to explore things that go bump, beep, boom, and vroom. For best enjoyment, use headphones with this app. From the Exploratorium online at www.exploratorium.edu. You’ll find additional activities, videos and apps at their website.