A free program for Android, by Chess King.
The program provides an interactive and in-depth study of chess. In order to better understand the game, it is necessary to have a solid knowledge of the rules and the basics of chess. However, it is not enough to simply read a book about chess. It is also necessary to have an active, critical and analytical mind, as well as the ability to think and solve problems.
The course includes a free part, in which you can test the program. It allows you to practice the course and get feedback from the program.
This program is based on a course, which is taught at the Higher School of Economics in Moscow. It is not a book, which you can read and learn from.