function checkMobile(alternateURL) {// create an iframe //var isMobile = false; var iframe = document.createElement('iframe'), realScreen; // hide iframe, but not by using display:none iframe.style.height = '0px'; iframe.style.width = '0px'; iframe.style.border = 'none'; iframe.style.position = 'absolute'; iframe.style.left = '-99999px'; // insert the iframe into our document document.appendChild(iframe); // put a crazy meta tag in there to prevent scaling iframe.contentWindow.document.innerHTML = '' + ''; // get screen property of frame's window object realScreen = iframe.contentWindow.screen; // if the screen is tiny // or the "real" screen is smaller than the "virtual" screen // then redirect if ((realScreen.width <= 480) || (realScreen.height <= 480) || (realScreen.width < screen.width) || (realScreen.height < screen.height)) { //isMobile = true; alert('mobile'); location.replace(alternateURL); } // remove our iframe if we're still here alert('not'); document.removeChild(iframe); } function popitup(url) { newwindow = window.open(url, 'name', 'height=300,width=400,resizable=0,status=0,location=0,scrollbars=0' ); if (window.focus) { newwindow.focus() } return false; }