Ghostview is an X11 interface for ghostscript 2.4 and later.  It features:

  - Ghostview parses any known version of Adobe's Document Structuring
    Conventions.
  - Page size is automatically determined from the Document Structuring
    Comments.  The user is able to override the values from the comments.
  - Window size is set to the bounding box for Encapsulated PostScript figures.
  - Default page size is Letter and can be changed via Xresources or
    application defaults file to A4 (or any other valid size) for our
    European friends.
  - Scrollbars appear when necessary.
  - Page orientation is automatically determined from the Document Structuring
    Comments.  The user is able to override the values from the comments.
  - Ability to view at 4 orientations: Portrait, Landscape, Upside-down,
    and Seascape (for those who rotate landscape the other direction).
  - Ability to restrict rendering to grayscale or monochrome.   (Requires
    ghostscript 2.6.1.)
  - Ability to mark pages for printing, or saving.  (Good for people that
    printed a 100 page document and lost page 59 due to a printer jam.)
  - Can popup zoom windows at printer resolution
    (1 display dot = 1 printer dot).

The Ghostview distribution includes a Ghostview Widget that people are
encouraged to use in other programs.