spHostUrl = decodeURIComponent(getQueryStringParameter('SPHostUrl'));
context = new SP.ClientContext.get_current();
parentContext = new SP.AppContextSite(context, spHostUrl);
web = parentContext.get_web();


var allLists = web.get_lists();


context.load(allLists);

context.executeQueryAsync(
    function() {


              alert(allLists);




    },
    function(sender, args) {
        alert(args.get_message());

    }
);