You depend on rocks for many things so wouldn’t it be nice to know more about them? This application provides a starting point for learning about rocks without being a course in geology. A small collection of common rocks is provided with photographs and descriptions. There are five quizzes of increasing difficulty, that you can use to test your knowledge about rocks, before or after, looking at the information provided. Most of this collection comes from Scotland but the same rock-types occur world-wide.

https://itunes.apple.com/us/app/common-rocks-reference/id301217333?ls=1&mt=8