Many companies use this software for editing photos.
I use this for our company work and this works perfectly for image editing process.
GIMP - GIMP is a multiplatform photo manipulation tool.
Wondershare PDFelement - All-in-one PDF editor
Affinity Photo - Affinity is the imaging and design suite for creative professionals exclusively for Mac.
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.
Krita - Krita is a professional FREE and open source painting program. It is made by artists that want to seaffordable art tools for everyone. Concept art. texture and matte painters, illustrations and comics.
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.