The MobileKey module comes with the following settings. These settings are found here:
Administer » Site configuration » MobileKey
Since you generally give one URL to your users, your home page (called Front Page in Drupal), it can be practical to send Mobile phone users to a special URL so when they access your site they see a better adapted front page than the usual.
The settings accept a local path (i.e. mobile) or a full path (i.e. http://mobile.example.com/).
Note that this gives you a way to use the ThemeKey capability to change the theme of all the pages that match "mobile/%" or that are accessed using a different domain name.
Technical detail: the redirection uses code 303 (i.e. See Other.)
IMPORTANT
Note that if you make use of static caches, this feature will not work with the default web server set up.
The feature sets a COOKIE named mk_device that can be checked by Apache2 to bypass the static cache if necessary: when the front page is accessed and mk_device is not set at all or has a value other than 'desktop,' then don't return the cached front page.