Need to tell if a user is browsing your site on an iPad? Here’s how to do so via PHP:

<?php
define('IS_IPAD', (bool)strpos($_SERVER['HTTP_USER_AGENT'],'iPad'));
?>

One can also do it via Javascript:

<script>
var IS_IPAD = navigator.userAgent.match(/iPad/i) != null;
</script>

However, I prefer making the determination server-side, as there’s a (small) number of users who browse with Javascript disabled, stylish in their tin-foil hats.