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.

Dabble Writer - Writing software for novelists.

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

SHAXPIR - A modern cloud workspace for fiction writing & worldbuilding

The Novel Factory - Helping to bring order to the chaos of creativity. Writing software that boosts productivity, saves time and helps you become a better writer. Packed with useful features and resources for novel writers.

Manuskript - Open-source tool for writers.