Mobile Detection

[MikeTrin]

There's a lot of info on changing a users theme if they are using a mobile browser. I'm looking to just change a few images and adsense code on various templates.

I have a taken some code out of init.php that vbulletin uses to detect various mobile browsers.

I'm trying to create a single global variable that I can use vb if condition on it from any template on any theme. I've seen the VB_Template:reRegister code that lets you push php variables to single templates but I need it go to any template.

So the question is, which hook and how do create a global variable that can be accessed from any template. I'ved attempted to use global $mobilemt as seen below in the global_bootstrap_init_start hook and {vb:raw mobilemt} in a template with no luck.

PHP Code:

global $mobilemt 

$mobilemt = "no"; 

if (stripos($_SERVER['HTTP_USER_AGENT'], 'windows') === false)  
    {  
        if (  
            preg_match('/(up.browser|up.link|mmp|symbian|smartphone|midp|wap|phone|android)/i', strtolower($_SERVER['HTTP_USER_AGENT']))  
            OR  
            stripos($_SERVER['HTTP_ACCEPT'],'application/vnd.wap.xhtml+xml') !== false  
            OR  
            ((isset($_SERVER['HTTP_X_WAP_PROFILE']) OR isset($_SERVER['HTTP_PROFILE'])))  
            OR  
            stripos($_SERVER['ALL_HTTP'],'OperaMini') !== false  
        )  
        {  
            $mobile_browser = true;  
        }  
        // This array is big and may be bigger later on. So we move it to a second if.  
        elseif (in_array(  
                    strtolower(substr($_SERVER['HTTP_USER_AGENT'], 0, 4)),  
                    array(  
                    'w3c ','acs-','alav','alca','amoi','audi','avan','benq','bird','blac',  
                    'blaz','brew','cell','cldc','cmd-','dang','doco','eric','hipt','inno',  
                    'ipaq','java','jigs','kddi','keji','leno','lg-c','lg-d','lg-g','lge-',  
                    'maui','maxo','midp','mits','mmef','mobi','mot-','moto','mwbp','nec-',  
                    'newt','noki','oper','palm','pana','pant','phil','play','port','prox',  
                    'qwap','sage','sams','sany','sch-','sec-','send','seri','sgh-','shar',  
                    'sie-','siem','smal','smar','sony','sph-','symb','t-mo','teli','tim-',  
                    'tosh','tsm-','upg1','upsi','vk-v','voda','wap-','wapa','wapi','wapp',  
                    'wapr','webc','winw','winw','xda ','xda-')  
                )  
            )  
        {  
            $mobile_browser = true;  
        }  
    }  

    if (  
        $mobile_browser  
        AND  
        preg_match('/(ipad|ipod|iphone|blackberry|android|pre\/|palm os|palm|hiptop|avantgo|plucker|xiino|blazer|elaine)/i', strtolower($_SERVER['HTTP_USER_AGENT'])) 
    )  
    {  
        $mobile_browser_advanced = true;  
    }  

    if ($mobile_browser_advanced||$mobile_browser) 
    { 
        { 
            $mobilemt="yes"; 
        } 
    }