function init(){

    // read / set guid cookie
    if ($.cookie("guid") == '' || $.cookie("guid") == null){
	var guid = jQuery.Guid.New();
	$.cookie('guid', guid, { expires: 365, path: '/', domain: 'theexperiments.com', secure: false});

    }	



    if((navigator.userAgent.match(/iPhone/i)) || (navigator.userAgent.match(/iPod/i)) || (navigator.userAgent.match(/iPad/i)) ) {
	is_Ios = 1;
    }

    nav_init();
}