Rehber Matematik is a free Android application developed by Synapsis Teknoloji under the Education and Reference category. This app is designed to help users make the most of Rehber Matematik books. It provides video solutions to all the questions in the book, and users can solve problems on the app when they don't have the book with them. The app also allows users to see their incorrect and unanswered questions and solve them again. To use the app, users need to create an account and activate their book by scratching the activation code on the back of the book. Once the book is activated, users can access any test or video solution they want. This app is available for free, regardless of where the book is purchased. Overall, Rehber Matematik is an excellent app for math enthusiasts who want to improve their knowledge and problem-solving skills.