Fantasia Archive - Free offline worldbuilding and story creation tool with dozens of templates, complex tagging options, document linking, and project-wide search. Template examples: characters, places, events, religions, currencies, magic, species, languages.

World Anvil - World Anvil is a worldbuilding tool for Authors, Storytellers and worldbuilding lovers.

Obsidian.md - A second brain, for you, forever. Obsidian is a powerful knowledge base that works on top of a local folder of plain text Markdown files.

Kanka.io - Kanka.

Campfire Pro - Character design, plot manipulation, and world-building tool for novelists and screenwriters.

Notebook.ai - A smart notebook that grows and collaborates with you