Angular: On/Off button

http://angularjs.org/

HTML

<script src="http://code.angularjs.org/angular-1.0.1.js"></script>
<div ng-app="myApp">
    <div ng-controller="myController">
        <button ng-click="flip()">{{on_off}}</button>
         <button ng-click="flip()">{{on_off}}</button>
    </div>
</div>

JavaScript

var myApp = angular.module('myApp', []);

myApp.controller('myController', ['$scope', function ($scope) {
    $scope.isOn = false;
    $scope.on_off = 'Off';
    $scope.flip = function () {
        $scope.isOn = !$scope.isOn;
        $scope.on_off= $scope.isOn ? 'On' : 'Off';
    };
}]);