Библия ЦС вер.4 is an Android application developed by Alexander Semeniuk. The app contains the text of the Old and New Testaments in Church Slavonic language, optimized for viewing on mobile devices. The app comes equipped with advanced navigation features such as daily readings, text search, and a visual calendar that makes it easier to navigate through the texts of the Bible.

The interface of the app has undergone significant changes compared to the previous version (ver.3), taking into account the latest requirements for the appearance and behavior of Android applications. Additionally, the app now includes a translation of the Bible into several languages for parallel reading. It is important to note that the app is distributed for informational purposes only and may contain typographical errors - hence, should not be used during worship or when writing scientific papers.

Overall, Библия ЦС вер.4 is a well-designed and user-friendly app for those who wish to read the Bible in Church Slavonic language on their mobile devices.