 <p>I work for InMobi. It's really easy to do this in PHP. First up, our tutorials are at <a href="http://developer.inmobi.com/wiki/index.php?title=PHP" rel="nofollow">http://developer.inmobi.com/wiki/index.php?title=PHP</a></p> <p>To display your own code when InMobi doesn't return an advert is simple.</p> <pre><code>// Use the MkhojAd.php file supplied require_once("MkhojAd.php"); // Use your unique Site ID $base = new MkhojAd("12345678901234567890"); $base-&gt;set_num_of_ads(1); if($base-&gt;request_ads()) { // The top ad echo $base-&gt;fetch_ad(); } else // No Advert Returned { // Your Alternative Advert Here } </code></pre>