4BOOK - GDZ Textbooks and Answer Keys of Ukraine is an Android application developed by 4BOOK.ORG Makarov Iliya. It is a full version educational and reference software that provides the most complete and high-quality answer keys (GDZ) and textbooks for schoolchildren ofclasses of Ukraine. The application offers a wide variety of solutions to homework assignments, including workbooks, laboratory and practical work, control and independent work on all subjects of the new school curriculum.

In the 4BOOK - GDZ app, parents and students can easily search for answers to problems, examples and exercises in Mathematics, English, Algebra, Geometry, Ukrainian, Physics, German and other subjects of the curriculum. The app also provides various settings such as favorites and choice of download directory, which helps to accomplish homework faster and save time for personal affairs.