Online Image Editor - Online editor for images and animated gifs with multiple effects and tools
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
Pixelitor - Pixelitor is a cross-platform raster graphics editor written in Java.
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.
RealWorld Photos - RealWorld Photos is an free portable photo editor for Windows.
Darktable - darktable is an open source photography workflow application and raw developer.