Энциклопедия Древо is an offline encyclopedia of open Orthodox Christianity, available for Android users. With over 30,000 articles and 18,000 illustrations, it covers a wide range of topics, including religious terms and concepts, church calendar, biographies of religious and historical figures, information on religious organizations, and articles on churches, monasteries, and necropolises. The app also features the complete text of the Russian Synodal Bible with parallel Church Slavonic translation, a biblical dictionary, Church Slavonic dictionary, and geographic and historical information. The app is free and does not contain any ads. The paid content only provides the option of voluntary donation to the developer. The app does not require an internet connection, but it allows the user to view high-quality illustrations, geographic maps, and third-party website pages referred to in the articles. The app is regularly updated, and the database is updated monthly. The app has a search function, day and night themes, adjustable font size, and an option to bookmark articles. However, it is important to note that the encyclopedia's content may contain inaccuracies, and the developer encourages users to provide feedback and corrections on the website or forum.