AdSense for mobile ads are precisely matched to the content of your mobile webpage using the same targeting technology as AdSense for content. Our crawlers scan the page to determine its content and then automatically serve ads that are relevant to what your visitors see.
In order for Google to properly target ads to your mobile website, our crawler needs to be able to access your mobile webpages. The phone useragent we use to crawl your site will contain the string "Mediapartners-Google", so please set up your web server to grant access to your mobile content any useragent that contains "Mediapartners-Google".
Please also be aware that Google will not be able crawl your webpages for ads targeting if you are restricting access to your mobile website to a specific set of IP addresses.