New Twiddle

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle'
});

helpers.my-helper.js

import Ember from 'ember';

export default Ember.Helper.extend({
  count: 0,
  timer: undefined,
  
  compute(params, hash) {
    clearInterval(this.get('timer'));
    setInterval(() => { this.recompute(); }, params[0] || 500);
    
    this.set('count', this.get('count') + 1);
    
    return this.get('count');
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
{{my-helper 500}}
{{my-helper 100}}
<br>
<br>

twiddle.json

{
  "version": "0.8.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.5.1",
    "ember-data": "2.5.2",
    "ember-template-compiler": "2.5.1"
  }
}