Inkpad - Inkpad - Vector illustration app for the iPad.
Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
Adobe Illustrator - Adobe Illustrator is a vector graphics editor.
SVGO - Tool for optimizing SVG files
SVGminify.com - Removes superfluous information reducing the size of SVG files
Affinity Photo - Affinity is the imaging and design suite for creative professionals exclusively for Mac.