Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
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.
GIMP - GIMP is a multiplatform photo manipulation tool.
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.
Affinity Photo - Affinity is the imaging and design suite for creative professionals exclusively for Mac.
Wondershare PDFelement - All-in-one PDF editor