Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Sketch - Professional digital design for Mac.
Affinity Designer - Professional creative software, exclusively for Mac.
Invision - Prototyping and collaboration for design teams
Adobe Illustrator CC - Adobe Illustrator CC is a commercial vector graphics editor.