Anaxis made a beautifull app for the Drupal Government Days event (http://www.drupalgovdays.org/). In this session they will show you how Android-apps can connect with Drupal sites.
In that way, the powerfull functionalities of the Drupal cms-system are combined with the well-known Android mobile offerings. Connect your smartphone or tablet with your Drupal-website and enjoy your website services on your mobile !!