What are some alternatives?
Storybird - Visual storytelling community
Manuskript - Open-source tool for writers.
Bhooks - A unique e-books platform & feedback community, with many helpful tools.
Scrivener - Scrivener is a content-generation tool for composing and structuring documents.
My Storybook - Make children's storybooks online for free.
Hemingway Editor - Hemingway App makes your writing bold and clear.