didUpdateAttrs hook

components.my-component.js

import Ember from 'ember';

export default Ember.Component.extend({
  didUpdateAttrs(options) {
   	console.log('I updated a value', options); 
  }
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  counter: Ember.Object.create({
    value: 1
  }),
  actions: {
  	click() {	this.get('counter').incrementProperty('value')
		}
	}
});

templates.application.hbs

{{my-component value=counter.value}}
<br>
<button {{action 'click' on='click'}}>click me</button>

templates.components.my-component.hbs

my value :: {{value}}

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"
  }
}