Edit in JSFiddle

function ContactsController() {
  var self = this;

  self.contacts = {
    name: "Thomas Awesome",
    address: "249 Union Avenue, Brooklyn"
  }

  self.changeAddress = function() {
    self.contacts.address = "28 W 245 New York";
  }

}


angular.module('MyApp', [])
  .controller('ContactsController', [ContactsController]);

// bootstraping the app
angular.element(document).ready(function() {
  angular.bootstrap(document, ['MyApp']);
})
<div class="container jumbotron">
  <div ng-controller="ContactsController as $ctrl">
    <p>
      Name: {{ $ctrl.contacts.name }}
      <br> Address: {{ $ctrl.contacts.address }}
    </p>
    <button class="btn btn-success" ng-click="$ctrl.changeAddress()">
      Change My Address
    </button>
  </div>
</div>