With the Zerigo add-on, setting up DNS for your custom domains is completely painless. Simply point your DNS to Zerigo's servers, and use the familiar Heroku commands for adding and removing hostnames. Your DNS settings will instantly update, and your domains will be ready to serve in no time.
Zerigo brings DNS management into the age of modern web apps.
When using the Zerigo add-on, Heroku will automatically keep your A Records up-to-date, so you will always be getting the most of our HTTP serving capacity.