WPtouch is a great plugin to convert your wordpress site into a mobile version. It renders a WordPress site in a format that looks like a native mobile app when it detects the browser user agent of a supported mobile device but many users of WPtouch free version are facing this problem. The problem is that after you add your Google Adsense publisher ID And custom channel ID in the WPtouch given fields, the ads are not displaying on mobile version of your website and if the ads are displaying, you cannot track the performance report.

View these threads to better understand the problem.

http://wordpress.org/support/topic/plugin-wptouch-how-to-add-adsense-code
http://wordpress.org/support/topic/plugin-wptouch-wptouch-doesnt-show-adsense

What is exactly the problem

I have been using AdSense for Content for a while. I have configured a custom channel for AdSense unit to keep tabs on the performance of individual ads.  Recently, I created my first AdSense for Mobile Content units. I linked each ad unit to a custom channel, as I do with my other AdSense placements. The ads display properly, each custom channel shows up when I list them, and each custom channel is linked correctly to one mobile AdSense placement. However, they aren’t showing up when I display a performance report.

On the main AdSense screen, I can see the number under “Page Views” increase when visitors see mobile AdSense units. However, when I click “View full reports” and “Custom channels,” I don’t see the custom channels that I created for the mobile ad units. I see all of the AdSense for Content, though.

A Little Solution

The AdSense implementation in WPtouch (as of version 1.9.24) is incorrect. Although it will display mobile ads, those ads will not be tracked properly under the custom channels that you create.

I resolved the issue by manually editing the file adsense-new.php, which by default is in wp-content/plugins/wptouch/include. Take out everything between these lines:
<?php echo '<div id="adsense-area">'; ?>

<?php echo '</div>'; ?>
Then, paste your AdSense for Mobile Content code between the two lines. The ads display properly AND are tracked in my custom channels.