How to Link Domain to a Bluemix app

you can't link a domain to a Bluemix app, you can link a subdomain to a Bluemix app. 

for Gymbirds.com i did a redirection from gymbirds.com to d.gymbirds.com the d.gymbirds.com is linked to gymbirds.ng.bluemix.net

 how to do that with Bluemix / Cloudfoundry ?

cf map-route gymbirds gymbirds.com -n d

"gymbirds" is the name of the App on Bluemix, "gymbirds.com" is the domain and "d" is the subdomain linked to the App

 So what's the new "grunt magic" ?

   changeroutebluemix: {
    command: function () {
     pkg = grunt.file.readJSON("package.json");
     var command =
      'cf map-route gymbirdstmp ng.bluemix.net -n gymbirds; ' +//map route gymbirds.ng.bluemix.net to gymbirds tmp
       'cf map-route gymbirdstmp gymbirds.com -n d; ' +
//map route d.gymbirds.com to gymbirdstmp
       'cf unmap-route gymbirds  ng.bluemix.net -n gymbirds; ' +
// unmap route gymbirds.ng.bluemix.net
       'cf unmap-route gymbirds  gymbirds.com -n d; ' +
// unmap route d.gymbirds.com
       'cf rename gymbirds gymbirds' + pkg.version + ' ;' +    
// rename app gymbirds into gymbirdslast
       'cf rename gymbirdstmp gymbirds'; 
// rename gymbirdstmp to gymbirds
     return command;
    }
   },