Plottr - The #1 rated visual book planning and series bible software for professional and aspiring writers.
LegendKeeper - LegendKeeper makes it easy to build immersive worlds for stories and RPG campaigns.
Kanka.io - Kanka.
CharacterHub - A social network designed for original characters, fan characters, and world-building.
Toyhouse - Toyhouse is a platform that allows users to build up characters foe their games and stories.
World Anvil - World Anvil is a worldbuilding tool for Authors, Storytellers and worldbuilding lovers.