Inject Ionic push in other controllers

According to the doc

I have to register my device token in run()

.run(function($ionicPlatform) {
$ionicPlatform.ready(function() {
var push = new Ionic.Push({
“debug”: true

push.register(function(token) {
  console.log("Device token:",token.token);
  push.saveToken(token);  // persist the token in the Ionic Platform


But can use new Ionic somewhere else? means in my other controller? I tried to inject but failed. Why the official doc is poorly written. :frowning: