Online Image Editor - Online editor for images and animated gifs with multiple effects and tools
Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
Pixelitor - Pixelitor is a cross-platform raster graphics editor written in Java.
SVGO - Tool for optimizing SVG files
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.
SVGminify.com - Removes superfluous information reducing the size of SVG files