Random House Digital has just released an iOS app, "Stephen Hawking's Snapshots of the Universe." The app explains some of the most popular physics experiments and principles. For example, how planets stay in orbit, how black holes are not strictly black, the gravitational deflection of light, relativity, how gravity and acceleration relate via the equivalence principle, and the evolution of the universe. There are eight experiments that both adults and students can conduct to learn the basic laws of physics in a fun and interactive way. Optimized for iOS 7, and released December 12, it's priced at US$4.99 and compatible with iPad.
Check It Out: Stephen Hawking's Snapshots of the Universe