title: Design app that supports both iOS8 and iOS7
body: <p>Suppose I want to design a master detail application, Xcode6 master-detail project template for universal app includes UISplitViewController and splitViewController is new in iOS8. I want to support app for iOS7 also.</p>
  
  <p>In general</p>
  
  <ol>
  <li>What is the best way to design an universal app using Xcode6
  storyboard that support both iOS8 and iOS7 ?</li>
  <li>Is it better to use separate story board for different OS version ?</li>
  <li>What are the best practices we should follow to make app compatible with both OS?</li>
  </ol>