digiKam - Professional Photo Management with the Power of Open Source
Saint Paint Studio - Saint Paint - The Essential Image Editor
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
Stet.io - Stet.io is a high-quality pixel management platform that allows editing the pictures with online commands or multiple options with real-time effects or filters.
XnView MP - XnView is a free software that allows you to view, resize and edit your images. It supports more than 500 different formats!
AliveColors - AliveColors is comprehensive graphics and photo editing software for Windows and Mac.