title: Are Heroku URLs dependable?
body: <p>I just deployed my first app to Heroku. I'm on the free tier, and the app is a little demo of a Ruby gem.</p>
  
  <p>Running <code>heroku open</code> sends me to a URL that looks something like <code>http://armored-magpie-3920.herokuapp.com</code>.</p>
  
  <ul>
  <li>Is this URL dependable, meaning I can link to it and expect it not to change?</li>
  <li>If not, is the IP dependable, so that I could register a domain name and point it there?</li>
  </ul>