PHP detect a mobile device and display code accordingly

<?php
function isMobileDevice() {
return preg_match("/(android|avantgo|blackberry|bolt|boost|cricket|docomo|fone|hiptop|mini|mobi|palm|phone|pie|tablet|up\.browser|up\.link|webos|wos)/i", $_SERVER["HTTP_USER_AGENT"]);
}

if(isMobileDevice()){
// mobile device is detected - make the link work so that users can dial directly from their phone
echo "Click to Call Us (000-000-0000)"; //add your <a> link
}
else {
// non mobile is detected - display the information without making it clickable
echo "Call Us (000-000-0000)";
}
?>