DocDroid - DocDroid is a service for sharing document and slides.
Wondershare PDFelement - All-in-one PDF editor
SlideShare - Discover, Share, and Present presentations and infographics with the world’s largest professional content sharing community.
Foxit PhantomPDF - Edit PDF files with our feature-rich PDF Editor. Download Foxit PDF Editor to convert, sign, scan / OCR & more. A speedy PDF Editor alternative to Adobe Acrobat.
DocSlide - DocSlide is an online document and knowledge sharing platform.
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.