Bluebeam PDF Revu is a feature-packed PDF editor, viewer and markup tool. It provides a number of user-friendly tools to handle anything you need to do with a PDF: from batch creation, conversion, editing and proofreading, highlighting and underlining and all kinds of marks, stamps, notes, signatures and editorial symbols, comments, etc.
Version 7.0 offers a number of improvements on previous versions including PDF spell check, a scan direct to PDF feature, file size reduction tool, and a variety of new markup tools like hatchmarks, arcs and curves, and new flags, among many others.