I don't think you're required to move anything, when you create an app and add the database you're given the db credentials and can access it from whatever you

I don't think you're required to move anything, when you create an app and add the database you're given the db credentials and can access it from whatever you want and it scales/bills independently from the hosting platform. There's also AWS: http://aws.amazon.com/rds/postgresql/ http://aws.amazon.com/rds/postgresql/