The purpose of the App is to provide the complete Year A, B, and C Sunday Lectionary scriptures that are normally only listed by their passages. In the past, the reader would look up the passages in the Book of Common Prayer for the applicable Year and date. Next they would individually open their Bible to the passage to obtain the reading.
By having the readings in the app database saves the reader from having to look these scriptures up. The database and supporting algorithms also provide a perpetual yearly calendar for all Sunday readings (forever).
To select the Revised Common Lectionary (RCL), click the Settings button, then slide the switch from BCP to RCL in the top right corner of the Settings display. You will need to close and reopen to app after changing the Lectionary setting.