Is a restful service needed to access/update a database?

I have a MySql database set up and a mobile app that should be able to write/read to and from the database.

The data being stored will be posts, comments, votes, etc.

Eventually, I might create a website that uses the same database.

My question is, do I need some sort of middleman (restful) service running or can I just connect straight to the MySql db from the client code (either the mobile app or website)?