Lightweight detector of mobile devices, OSs & browsers (PHP)

mobile_detector.php

<?php

/*
 * Lightweight detector of mobile devices, OSs & browsers
 * Copyright 2012  Túbal Martín  (email: tubalmartin@gmail.com)
 * License: GPL2
 */

if ( ! function_exists('mobile_detector') )
{
    // Global vars
    $is_mobile = false;
    $is_iphone = $is_ipad = $is_kindle = false;
    $is_ios = $is_android = $is_webos = $is_palmos = $is_windows = $is_symbian = $is_bbos = $is_bada = false;
    $is_opera_mobile = $is_webkit_mobile = $is_firefox_mobile = $is_ie_mobile = $is_netfront = $is_uc_browser = false;


    function mobile_detector($debug = false)
    {
        global $is_mobile;

        // Check user agent string
        $agent = isset($_SERVER['HTTP_USER_AGENT']) ? $_SERVER['HTTP_USER_AGENT'] : '';

        if (empty($agent)) {
            return;
        }

        $mobile_devices = array(
            'is_iphone' => 'iphone',
            'is_ipad' => 'ipad',
            'is_kindle' => 'kindle'
        );
        
        $mobile_oss = array(
            'is_ios' => 'ip(hone|ad|od)',
            'is_android' => 'android',
            'is_webos' => '(web|hpw)os',
            'is_palmos' => 'palm(\s?os|source)',
            'is_windows' => 'windows (phone|ce)',
            'is_symbian' => 'symbian(\s?os|)|symbos',
            'is_bbos' => 'blackberry(.*?version\/\d+|\d+\/\d+)',
            'is_bada' => 'bada'
        );
        
        $mobile_browsers = array(
            'is_opera_mobile' => 'opera (mobi|mini)', // Opera Mobile or Mini
            'is_webkit_mobile' => '(android|nokia|webos|hpwos|blackberry).*?webkit|webkit.*?(mobile|kindle|bolt|skyfire|dolfin|iris)', // Webkit mobile
            'is_firefox_mobile' => 'fennec', // Firefox mobile
            'is_ie_mobile' => 'iemobile|windows ce', // IE mobile
            'is_netfront' => 'netfront|kindle|psp|blazer|jasmine', // Netfront
            'is_uc_browser' => 'ucweb' // UC browser
        );
        
        $groups = array($mobile_devices, $mobile_oss, $mobile_browsers);
        
        foreach ($groups as $group) {
            foreach ($group as $name => $regex) {
                if (preg_match('/'.$regex.'/i', $agent)) {
                    global $$name;
                    $is_mobile = $$name = true;
                    break;
                }
            }
        }
        
        // Fallbacks
        if ($is_mobile === false) {
            $regex = 'nokia|motorola|sony|ericsson|lge?(-|;|\/|\s)|htc|samsung|asus|mobile|phone|tablet|pocket|wap|wireless|up\.browser|up\.link|j2me|midp|cldc|kddi|mmp|obigo|novarra|teleca|openwave|uzardweb|pre\/|hiptop|avantgo|plucker|xiino|elaine|vodafone|sprint|o2';
            $accept = isset($_SERVER['HTTP_ACCEPT']) ? $_SERVER['HTTP_ACCEPT'] : '';

            if (false !== strpos($accept,'text/vnd.wap.wml')
                || false !== strpos($accept,'application/vnd.wap.xhtml+xml')
                || isset($_SERVER['HTTP_X_WAP_PROFILE'])
                || isset($_SERVER['HTTP_PROFILE'])
                || preg_match('/'.$regex.'/i', $agent)
            ) {
                $is_mobile = true;
            }
        }

        // DEBUGGER OUTPUT
        if ($debug === true) {
            echo '<strong>User Agent: '.$agent.'</strong><br>';
            foreach ($GLOBALS as $k => $v) {
                if (strpos($k, 'is_') !== false) {
                    echo '<span style="color:'.($v ? 'green':'red').';">$'.$k.'</span><br>';
                }
            }
        }

    }

    // execute inmmediatly
    mobile_detector();

}