Plot Factory - Online story planner, organizer, and writing application.
World Anvil - World Anvil is a worldbuilding tool for Authors, Storytellers and worldbuilding lovers.
World Scribe - World Scribe is a platform that eases the creation process if novel and allows users to keep track of important elements in their world.
Scrivener - Scrivener is a content-generation tool for composing and structuring documents.
Notebook.ai - A smart notebook that grows and collaborates with you
Notebooks by DroidVeda LLP - Notebooks is an app by DroidVeda LLP that comes up with features to help you in creating customizable digital notebooks so you can take notes as well as can also attach drawings to notes.