JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://code.angularjs.org/angular-1.0.1.js"></script>
<div ng-app="myApp" ng-controller="FirstCtrl">
<input type="number" ng-model="data.age">
<h1>{{data.age}}</h1>

<input type="button" value="Change to 20" ng-model="data" onclick="change()">

JavaScript

var person = {
    age: 16
};

// Create module
var myApp = angular.module('myApp', []);
myApp.factory('Data', function() {
    return person;
});

function FirstCtrl($scope, Data) {
    $scope.data = Data;
}

function change() {
    var appElement = document.querySelector('[ng-app=myApp]');
    var $scope = angular.element(appElement).scope();
    $scope.$apply(function() {
        $scope.data.age = 20;
    });
}