Wondershare PDFelement - All-in-one PDF editor
Foxit Reader - Foxit Reader is a free and light-weight multi-platform PDF document viewer.
Google Docs - Create a new document and edit with others at the same time -- from your computer, phone or tablet. Get stuff done with or without an internet connection. Use Docs to edit Word files. Free from Google.
Nitro Pro - An affordable Adobe Acrobat alternative for editing and creating PDF
PDF-XChange Editor - The smallest, fastest, most feature-rich PDF editor/viewer available
Smallpdf - PDF document management and conversion suite