POINT - Awesome link sharing/commenting with friends.
Wondershare PDFelement - All-in-one PDF editor
LiquidText - LiquidText improves upon the reading experience by allowing users to better synthesize, visualize and collaborate over digital text.
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.
Stellate.co - Everything you need to run your GraphQL API at scale
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.