Question

Google has indexed my Heroku app subdomain: myapp.heroku.com

Is it duplicate content?

How should I redirect myapp.heroku.com to mydomain.com?

Answer 1

Use the Heroku add-on custom domains:

heroku addons:add custom_domains:basic
heroku domains:add www.myapp.com
heroku domains:add myapp.com

In addition, you have to take some configuration steps at the admin interface of your domain provider. You need a CNAME to proxy.heroku.com and three A-RECORDs to the Heroku IPs. You find this in the Heroku Docs.

Edit to respond to another answer below. You can redirect myapp.com to http://www.myapp.com in your routes.rb:

 constraints(:host => /^communityguides.eu/) do
    root :to => redirect("http://www.communityguides.eu")
    match '/*path', :to => redirect {|params| "http://www.communityguides.eu/#{params[:path]}"}
  end