Back like button on Phonegap w/ AngularJS

phonegap_back.js

// add a element with id="homegap" on the template home of the app

app_helper = {
	initialize: function() {
        this.bindEvents();
    },
    bindEvents: function() {
        document.addEventListener('deviceready', this.onDeviceReady, false);
    },
    onDeviceReady: function(){
        // back button exit the app
		document.addEventListener("backbutton", app_helper.onBackKeyDown, false);
	},
    onBackKeyDown: function(){
        var homepage = document.getElementById('homepage');
        if (homepage){
            navigator.app.exitApp();
        }else{
            navigator.app.backHistory();
        }    	
    },
};

app_helper.initialize();