Wondershare PDFelement - All-in-one PDF editor
MJML - The open source framework for responsive emails
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.
Stripo - Stripo is an all-in-one email design platform. We enable our clients to build emails of any complexity, including interactive AMP emails, really fast and easy.
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.
Templates by Email Monster - Hundreds of free, responsive email templates. Pick and edit.