Freeplane began as a fork of the Freemind project. While maintaining comparability with Freemind file format, it has far outpaced in features and development. As of 3/5/2022, the latest Freeplane update (1.9.3) is 3/5/2022 vs Freemind was last updated (1.0.1) 2/5/2016. Active, helpful community.
Inkscape - Inkscape is a free, open source professional vector graphics editor for Windows, Mac OS X and Linux.
Xmind - Xmind is a brainstorming and mind mapping application.
Sketch - Professional digital design for Mac.
FreeMind - FreeMind is a premier free mind-mapping software written in Java.
Affinity Designer - Professional creative software, exclusively for Mac.
vym - VYM (View Your Mind) is a tool to generate and manipulate maps which show your thoughts.