I could not find the docs. Does it offer a static storage URI for people to download stuff via a link? Can I update the contents of the storage URI without generating a new URI everytime?
Yes. By default all your files are private and only you can access them. To make a public url you can use f0.publish('filename'); This returns a static url that you can share with anyone, and they can download the file.
This url will stay valid until the file is deleted or unpublished via f0.unpublish('filename');
If you call publish again, it will generate a new public URL.