Making existing UIViewControllers in Storyboard as master & detail
I have two UIViewControllers already designed in XCode Storyboard file. All I need to do is create a UISplitViewController and make one of them master and other detail. I can't find a way to do that in Storyboard.
Solution
Yes you can make it
Add UISplitViewController into storyboard. You find master UINavigationController with UITableViewController as RootViewController
Delete the root segue between NavigationController and UITableViewController
Make segue From UINavigationController to your first UIViewController as root View Controller of UINaviagtionController
Then Delete the default detail Controller of UISplitViewController
Make segue from UISplitViewController to your second UIViewController
From RelationShip Segue's select secondary view controller to make second UIViewController as detail view controller