ใช้ $_SERVER[‘HTTP_USER_AGENT’] ครับ ตรวจสอบ Web Browser

<?php

$agent = $_SERVER['HTTP_USER_AGENT'];

if(preg_match('/iPhone|Android|Blackberry/i', $agent)){
    header("location:http://m.cymiz.com");
    exit;
}

?>

เขียนที่ .htaccess ง่ายกกว่า

RewriteCond %{REQUEST_URI} !^/mobiledirectoryhere/.*$
RewriteCond %{HTTP_USER_AGENT} "android|blackberry|ipad|iphone|ipod|iemobile|opera mobile|palmos|webos|googlebot-mobile" [NC]
RewriteRule ^(.*)$ /mobiledirectoryhere/ [L,R=302]

อีกวิธี

RewriteEngine On

# Check if this is the noredirect query string
RewriteCond %{QUERY_STRING} (^|&)noredirect=true(&|$)
# Set a cookie, and skip the next rule
RewriteRule ^ - [CO=mredir:0:%{HTTP_HOST},S]

# Check if this looks like a mobile device
# (You could add another [OR] to the second one and add in what you
# had to check, but I believe most mobile devices should send at
# least one of these headers)
RewriteCond %{HTTP:x-wap-profile} !^$ [OR]
RewriteCond %{HTTP:Profile} !^$
# Check if we're not already on the mobile site
RewriteCond %{HTTP_HOST} !^m\.
# Check to make sure we haven't set the cookie before
RewriteCond %{HTTP:Cookie} !\smredir=0(;|$)
# Now redirect to the mobile site
RewriteRule ^ http://m.example.org%{REQUEST_URI} [R,L]

อีกตัว

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress

Options +FollowSymlinks
RewriteEngine on
RewriteBase /

# prevent looping
RewriteCond %{HTTP_HOST} !^m.mysite.com$

# if the browser accepts these mime-types, it's definitely mobile, or pretending to be
RewriteCond %{HTTP_ACCEPT} "text\/vnd\.wap\.wml|application\/vnd\.wap\.xhtml\+xml" [NC,OR]

# a bunch of user agent tests
RewriteCond %{HTTP_USER_AGENT} "sony|symbian|nokia|samsung|mobile|windows ce|epoc|opera" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "mini|nitro|j2me|midp-|cldc-|netfront|mot|up\.browser|up\.link|audiovox"[NC,OR]
RewriteCond %{HTTP_USER_AGENT} "blackberry|ericsson,|panasonic|philips|sanyo|sharp|sie-"[NC,OR]
RewriteCond %{HTTP_USER_AGENT} "portalmmm|blazer|avantgo|danger|palm|series60|palmsource|pocketpc"[NC,OR]
RewriteCond %{HTTP_USER_AGENT} "smartphone|rover|ipaq|au-mic,|alcatel|ericy|vodafone\/|wap1\.|wap2\.|iPhone|android"[NC]

# rewrite rules here
RewriteRule ^(.+)\$ http://m.mysite.com/$1 [R=302,NC]

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