How to set splitView controller to work on iPad only in Xcode 6 in a universal app

In previous versions of Xcode, I would create two separate storyboards and allow the iPad version of the application to be presented and the other to represent the iPhone version of the iPhone. Now I'm not sure what to do. I thought I would create a split view controller and somehow indicate when to use that split view controller using the width and height options found at the bottom. I believe, however, that this is only used for things inside viewControllers.

Or I would create a split view in the same storyboard and somehow indicate that it should be the initial view controller if the device is an iPad, perhaps programmatically

BOOL iPad = ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad );
if (iPad){
    // use iPad SplitVC
}