PDFpen - PDFpen is a PDF editor to add text, images, and signatures to PDFs.
Beyond Compare - Beyond Compare allows you to compare files and folders.
Adobe Reader - Adobe Acrobat Reader is a free tool for viewing documents that have been stored in Adobe's Portable Document Format (PDF).
WinMerge - WinMerge is an open source differencing and merging tool for Windows.
Adobe Acrobat DC - Make your job easier with Adobe Acrobat DC, the trusted PDF creator. Use Acrobat to convert, edit and sign PDF files at your desk or on the go.
Meld - What is Meld? Meld is a visual diff and merge tool targeted at developers.