Plot Factory - Online story planner, organizer, and writing application.
Aeon Timeline - "The timeline tool for creative thinking. Capture, create and explore ideas."
World Anvil - World Anvil is a worldbuilding tool for Authors, Storytellers and worldbuilding lovers.
Preceden - Preceden makes it easy to build simple, powerful timelines
Scrivener - Scrivener is a content-generation tool for composing and structuring documents.
Timeline - Timeline is a cross-platform application for displaying and navigating events on a timeline.