Vectr

Vectr is a free graphic editor used to create vector graphics and illustrations easily and intuitively.

It's a powerful web and desktop multi-platform tool that even allows you to instantly share designs with other users (for example, for further collaboration), in real time without waiting. This way, others can watch you create or edit projects live, whether you're logged in to the web app or working in the desktop version of the program.

Sharing is done by sending the project link to the people in question, who can then follow your creation in real time via that link.