This program allows filling the limitations of the Preview.app of MacOs with the following improvements:

Allows refreshing the display of a pdf document keeping the exact initial position.
- The previous version can be displayed for comparisons. Main changes between updated version and previous one can be highlighted.
- The windows focus can be enabled and disabled after a pdf refresh event.
- A full night mode with PDF display is available.
- A preview display of link..

In addition, it adds the other features:
Special popup zoom on images by extracting the source image in the pdf code
- LiveCam display to make presentation with presenter view.
- Spell check
- Annotations import and export with export in txt format useful to address reviews and special edition frame.
- Bookmark of PDF files available from status bar menu and main document windows.
- Link bibliographic references by using regular expression.