When I am authoring a document in Emacs, such as a report or my CV, it is useful for me to compile the source file periodically to see what the resulting file PDF looks like. I used to run a separate PDF viewer to look at the output, but I now have a complete Emacs solution.
The editing environment
When writing a document, I usually want the output to be a PDF file. Accordingly, I put the following in my .emacs file.
(setq TeX-PDF-mode t)
I then split my Emacs frame into two buffers vertically, using C-x 3 (see screencast below). After compiling my file with C-c C-c, I visit the resulting PDF file in the other Emacs window. The Emacs doc-view package will display the PDF file.
Including auto-revert functionality
The final piece to the puzzle is to set files visited in doc-view-mode to auto-revert when changed on disk. That way, then I update my file and recompile with C-c C-c, the PDF in the other window will automatically update.
This is achieved by placing the following line in my .emacs.
(add-hook 'doc-view-mode-hook 'auto-revert-mode)
Here is a screencast of this process in action.
This is a simple setup that I use to author reports, edit them, and see immediate updates to my output file without leaving Emacs.