NIOS Books and NIOS Board Exam is an Android application developed by Jack Rehan, available for free download. The app is a comprehensive guide to NIOS exams, including Sr. Secondary, Secondary, and Diploma in Elementary Education (D.El.Ed) exams in Hindi and English. The app provides chapter-wise PDF notes for NIOS exam preparation and offline content for easy accessibility.

The app includes material and books for NIOS exam preparation, including courses in Hindi, English, Bengali, Sanskrit, mathematics, physics, chemistry, biology, history, geography, political science, economics, business studies, accountancy, home science, psychology, computer science, sociology, painting, mass communications, data entry operations, environmental science, tourism, introduction to law, library and information science, and भारतीय ज्ञान परंपरा. The app also offers vocational courses and open basic education for NIOS exam preparation.