Scriptsure is a scriptwriting web application that combines the ease and aesthetics of Medium with the functional writing experience of Final Draft. As a playwright, I was really frustrated with how there didn't seem to be any scriptwriting options that were web-based, aesthetically pleasing to work in, and intuitively functional. Many apps came close, but were always missing one or another functionality that made it a deal-breaker.
Scriptsure is a single-page web application built using a React/Redux/Rails stack. You can find the repo for the API here.
I also used Draft.js to create the editor for the application. Used Custom block styles and custom keybindings to create a user experience that allows writers to control all of the formatting controls of the editor without leaving the keyboard.