Google has a great story writing tool : Google Story Builder
It’s actually a fun tool that students from all levels can use to improve their writing skills as they are creating their own stories in a unique way.
Google Story Builder doesn’t ask you to have an account, you simply start writing the names of the characters in your story and writing what they are saying or editing lines of dialogues in a word document style. When you are done, write the title and choose your music. You can watch and listen your story and share it with others.
How to use it:
An easy and fun tool---give it a try.