<script>
function detectmob() {
if( navigator.userAgent.match(/Android/i)
|| navigator.userAgent.match(/webOS/i)
|| navigator.userAgent.match(/iPhone/i)
|| navigator.userAgent.match(/iPad/i)
|| navigator.userAgent.match(/iPod/i)
|| navigator.userAgent.match(/BlackBerry/i)
|| navigator.userAgent.match(/Windows Phone/i)
){
return true;
}
else {
window.location.href = 'http://www.google.com/';
}
}
</script>

Bu Kadar Basit