Liber Pro takes the 1961 Liber Usualis, a book of over 2,300 pages of Gregorian Chant for use throughout the liturgical year, and literally puts it at your fingertips on your iPhone, iPad, or iPod Touch. Liber Pro adds to this tome a linked table of contents, user-defined bookmarks, vertical and horizontal paging and zooming, browser-like navigation, a dynamic liturgical calendar, and more.

Liber Pro is more than just an eBook. It is also a complete 1961 Roman Calendar, capable of calculating the moveable feasts throughout the year automatically. This means you can select a date; view the proper, common, and feria for that date; and jump instantly to the relevant pages in the Liber Usualis.

FEATURES:
Browser:
- 1961 Liber Usualis: over 2,300 pages
- Scroll, zoom, and page with touch gestures
- Simple “Back” and “Forward” buttons traverse browsing history
- Browse in portrait or landscape orientation
- Option to hide view selector for additional viewing area
- Selectable paging direction: up and down or left and right
- Selectable overlay eases page viewing
- Two-finger tap brings up markup palette (In-App Purchase Required)

Calendar:
- Calculates the day’s feast from the calendar of 1961
- Links to the starting page of the proper, common, and feria of the day
- Select today, the next or previous day, the next or previous week, or choose a day with a date picker

Bookmarks:
- User-defined bookmarks retain page, position, and zoom
- List of bookmarks can be reordered and individual bookmarks deleted

Table of Contents:
- Extensive table of contents provides links to Masses, offices, rubrics, and much more

History:
- Provides links to the 100 most recently visited pages this session

Search:
- Text-based search of the Liber
- Tap a search result to jump to the page

Annotations:
- iPhone/iPod
- Three drawing tools plus selection tool
- Freeform or four-point-fill drawing modes
- Four colors available plus ability to white page text out
- iPad
- Includes all annotation features available for iPhone/iPod
- Additional highlighter tool
- Four point line-to mode
- Twelve color palette