Flexor Apps let Users post stuff to the service.
Each App has two parts:
The Composer is the interface for creating a post. It can be anything that results in a post object being made.
The composerURL field of an app should point to an HTML page that will be rendered in an iFrame in the Flexor app. Communication between the Composer page and the Flexor app is done via Javascript postMessage messages.
The Renderer is the interface for displaying a post. This is only used on the view Post page and is optional. The default Flexor renderer is used when displaying a post elsewhere or when the rendererURL field is empty.
The rendererURL field of an app should point to an HTML page that will be rendered in an iFrame in the Flexor app.