XnView MP - XnView is a free software that allows you to view, resize and edit your images. It supports more than 500 different formats!
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.
IrfanView - IrfanView ... one of the most popular viewers worldwide.
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.
Imgseek - imgSeek is a collection of free open source projects for searching a collection of images using...
Wondershare PDFelement - All-in-one PDF editor