The Simple Mobile Detection plugin does a simple check to see if clients are on a mobile device. If so, this is stored in the User State so that you can check anywhere in your code if you’re dealing with a mobile client.
The Mobile Detection plugin uses the default Joomla Browser class and extends it with detection for iPad, iPhone, iPod and Android devices. The Joomla iPad detection and iPhone or iPod detection will store on what device the client is currently viewing the website. The Joomla Android detection is a little more advanced and also attempts to collect more information about the device, like the model and the Android build.
Download Simple Mobile Detection plugin: http://bloorum.com/threads/simple-mobile-detection-plugin-for-joomla.2145/
Simple Mobile Detection plugin for Joomla