Chữa Bài Tập is a free Android application developed by DTL Group that serves as a useful reference book for students from grade 1 to 12. It offers a rich collection of exam papers, all with detailed answers and explanations, that are continuously updated and carefully selected by teachers from all over the country. The app is simple, user-friendly, and contains a complete set of multiple-choice questions for all subjects and tests. It also features a real-time exam mode that automatically grades and scores the test papers after submission.

The app is designed to help students learn and revise more effectively with its comprehensive collection of exercises, theories, and exam papers, all of which are in line with the school curriculum. The app includes a concise theoretical system, a complete set of multiple-choice questions, and exam papers that closely follow the school curriculum. The app's easy-to-use interface and extensive collection of exercises make it an excellent tool for students to study in advance or review their lessons.