JavaScript Singletons and Module Pattern [closed]

Is there a preferred way of doing what I describe here. I want to namespace my JavaScript code and use the Singleton Pattern so that only one instance of my JavaScript app exists.

I have seen two approaches to this in JavaScript. One which simply returns and object literal, and another which uses the Revealing Module Pattern. If all I want is a singleton object (not caring about enforcing faux public/private methods and properties) is returning an object literal the way to go?

// Approach 1
var AppOne = (function(){
  return {
    Util: {
      init: function() {
        $("body").append("<strong>AppOne.Util initiliased</strong><br>");
      }
    },
    Ajax: {
      init: function(){
        $("body").append("<strong>AppOne.Ajax initialised</strong><br>");
      }
    }
  };
})();

// Approach 2
var AppTwo = (function(){
  var Util = function() {
    return {
      init: function() {
        $("body").append("<strong>AppTwo.Util initialised</strong><br>");
      }
    };
  }();

  var Ajax = function() {
    return {
      init: function() {
        $("body").append("<strong>AppTwo.Ajax initialised</strong><br>");
      }
    };
  }();

  return {
    Util: Util,
    Ajax: Ajax
  };
})();

AppOne.Util.init();
AppOne.Ajax.init();

AppTwo.Util.init();
AppTwo.Ajax.init();