title: Checking if user's device is ipad or iphone/ipod, difference between two ways
body: <p>I'm reading <code>Apress - Beginning iPad Development for iPhone Developer Mastering the iPad SDK</code> and in one chapter i read about device checking and author write: </p>
  
  <p><em>"Although you may be temped to simply check the user's device type or operating system version, with Apple constantly releasing new devices and iOS versions, that's not the way to go. A better approach is to test for the availability of exclusive iPad classes using NSClassFromString. If you pass an iPad-only class name, such as UISplitViewController to NSClassString and a valid object is returnet, you'll know user's device is an iPad.."</em></p>
  
  <p>I don't understand, why simply check device type for example by:</p>
  
  <pre><code>  NSString *device = [[UIDevice currentDevice] model];
  
    if ([device rangeOfString:@"iPad"].location != NSNotFound ) {
          isIPad = true;
    }
    else isIPad = false;
  </code></pre>
  
  <p>Is worse than checking ipad classes?</p>