php判断安卓、苹果设备的代码

<?php
    $userAgent = $_SERVER['HTTP_USER_AGENT'];
    if(strpos($userAgent,"iPhone") || strpos($userAgent,"iPad") || strpos($userAgent,"iPod")){
        echo '这是苹果公司的产品';
    }else if(strpos($userAgent,"Android")){
        echo '这是安卓系统产品';
    } else{
        echo 这是其它东西';
    }
?>