Православни црквени календар is an Android app that provides users with an extensive collection of prayers, psalms, akathists, canons, troparia, and the Orthodox Church calendar. The app includes daily troparia, general troparia, and Easter troparia for the whole year. The app also features the Orthodox Church calendar with fasting dates and the lives of the Saints. The app automatically adjusts movable holidays and fasts according to Easter. Additionally, the app includes several useful tools such as a calculator for the date of Orthodox Easter, a date converter, and a calculator for fasting periods and trapava sedmica.

The app's interface is user-friendly, and the app is easy to navigate. The app also includes a widget that is 4x2 in size. It is important to note that users should consult with their spiritual leaders regarding fasting rules. Overall, Православни црквени календар is a useful app for Orthodox Christians looking to stay connected to their faith and observe important religious dates and practices.