Block won't display on the iPhone

I'm trying to use this module to allow iPhone users to switch to the "full site" theme. The module works beautifully, but for some reason the block with the theme selections form won't display on the iPhone.

I did a little troubleshooting by placing some various elements like the Powered by Drupal image and the Primary Links blocks in the same region, and they display just fine on the iPhone. I even checked in the database in the blocks table, and the values are the same for the Switchtheme block and the ones that displayed properly. Any advice on how to further troubleshoot this would be great.