SharePoint 2013 - How to get AppWeb Info from App

First create SharePoint Hosted App using Visual Studio 2012 and add below given html control in default.aspx page

 < div>
        < p id="message1">
            initializing...
        < /p>
    < /div>
    < div>
        < p id="percentHTML">
            initializing..................
        < /p>
    < /div>
    < p id="hostWebURL">< /p>
    < p id="appWebURL">< /p>

    < div id="message">
    < /div>
    < p id="currentWebText">< /p>
    < ul id="listTree">
    < /ul>

    < div id="addItemPanel" style='display: none'>
        Item Title:
        < input type="text" name="itemTitle" title="Item Title" id="itemTitle" />
        < a href="javascript:createListItem()">Create List Item< /a>
    < /div>


Replace App.js as below


'use strict';

var context = SP.ClientContext.get_current();
var user = context.get_web().get_currentUser();
var oWebsite;
var collList;
var clientContext;




// This code runs when the DOM is ready and creates a context object which is needed to use the SharePoint object model
$(document).ready(function () {
    getUserName();
    //drawTable();
    retrieveWebSiteProperties();
});

// This function prepares, loads, and then executes a SharePoint query to get the current users information
function getUserName() {
    context.load(user);
    context.executeQueryAsync(onGetUserNameSuccess, onGetUserNameFail);
}

// This function is executed if the above call is successful
// It replaces the contents of the 'message' element with the user name
function onGetUserNameSuccess() {
    $('#message1').text('Hello ' + user.get_title());
}

// This function is executed if the above call fails
function onGetUserNameFail(sender, args) {
    alert('Failed to get user name. Error:' + args.get_message());
}

function retrieveWebSiteProperties() {
    clientContext = new SP.ClientContext.get_current();
         
    oWebsite = clientContext.get_web();
    clientContext.load(oWebsite, 'Title', 'Created');
         

    collList = oWebsite.get_lists();
    clientContext.load(collList, 'Include(Title, Id)');

    clientContext.executeQueryAsync(
        Function.createDelegate(this, onQuerySucceeded),
        Function.createDelegate(this, onQueryFailed)
    );
}

function onQuerySucceeded(sender, args) {
    var message = 'Title: ' + oWebsite.get_title() +
        ' Created: ' + oWebsite.get_created();

    document.getElementById("message").innerText = message;

    //display lists
    var listEnumerator = collList.getEnumerator();
    var listTree = document.getElementById("listTree");
    while (listEnumerator.moveNext()) {
        var oList = listEnumerator.get_current();
        var listTitle = oList.get_title();
        var li = document.createElement("li");
        li.id = listTitle;
        li.appendChild(document.createTextNode(listTitle));
        listTree.appendChild(li);
        if (listTitle == "CustomList1") {
            getListItems();
        }
    }
}

function getListItems() {
    //alert('getting list items');
    var oList = clientContext.get_web().get_lists().getByTitle('CustomList1');

    var camlQuery = new SP.CamlQuery();
   camlQuery.set_viewXml(
        '< View>< Query>< Where>< Geq>< FieldRef Name=\'ID\'/>' +
        '< Value Type=\'Number\'>1< /Value>< /Geq>< /Where>< /Query>' +
        '< RowLimit>25< /RowLimit>< /View>'
    );
    this.collListItem = oList.getItems(camlQuery);

    clientContext.load(collListItem);
    clientContext.executeQueryAsync(
        Function.createDelegate(this, this.onItemsGetQuerySucceeded),
        Function.createDelegate(this, this.onQueryFailed)
    );

}

function onQueryFailed(sender, args) {
    console.log('Request failed. ' + args.get_message() +
        '\n' + args.get_stackTrace());
}


function createListItem() {

    var oList = clientContext.get_web().get_lists().getByTitle('CustomList1');

    var itemCreateInfo = new SP.ListItemCreationInformation();
    this.oListItem = oList.addItem(itemCreateInfo);
    oListItem.set_item('Title', document.getElementById("itemTitle").value);
    oListItem.update();

    clientContext.load(oListItem);
    clientContext.executeQueryAsync(
        Function.createDelegate(this, this.onItemCreateQuerySucceeded),
        Function.createDelegate(this, this.onQueryFailed)
    );
}


function onItemsGetQuerySucceeded() {
    var listItemEnumerator = collListItem.getEnumerator();

    var cl = document.getElementById("CustomList1");
    while (cl.childNodes.length > 0) {
        cl.removeChild(cl.childNodes[0]);

    }
    cl.textContent = cl.id;
    var ul = document.createElement("ul");;
    while (listItemEnumerator.moveNext()) {
        var oListItem = listItemEnumerator.get_current();
        var li = document.createElement("li");
        li.appendChild(document.createTextNode("Title:" + oListItem.get_item('Title') + " Title: " + oListItem.get_item('Title')));
        ul.appendChild(li);
    }
    cl.appendChild(ul);
    var div = document.createElement("div");
    div.innerHTML = document.getElementById("addItemPanel").innerHTML;
    cl.appendChild(div);
}

function onItemCreateQuerySucceeded() {
    //alert('Item created: ' + oListItem.get_id());
    getListItems();
}