title: CodeIgniter mobile OS detection
body: <p>I've been able to detect what mobile device a user is using with CodeIgniter, but I haven't been able to detect what operating system the current mobile device is running.</p>
  
  <p>Let's say someone is using a Samsung mobile device that runs on Android, and another is using a normal Java mobile operating system that's still Samsung. How can I check to see the which operating system each user is on?</p>