Key: Rocks (com.bim.key.rocks) on Google Play
This app is for rock enthusiasts and students of earth science.The app lists out common 46 rocks with their detail information. You can you key out the rocks based on their color, texture ..., and learning the rocks by browse, question or quiz Functions: browse rocks. detail information for each rock with pictures. key out the rock based on their information. practice questions with an answer and hints. quiz with timer. option to save quiz for review. setting: select rocks and/or particular attribute for question and quiz.