Use following snippet to do it on iOS 8 onwards:
For Objective C:
UIViewController *walkThru = [self.storyboard instantiateViewControllerWithIdentifier:@"WalkThroughScene"];
walkThru.providesPresentationContextTransitionStyle = YES;
walkThru.definesPresentationContext = YES;
[walkThru setModalPresentationStyle:UIModalPresentationOverCurrentContext];
[self.navigationController presentViewController:walkThru animated:YES completion:nil];
For Swift 2 :
let viewController : XYZViewController = self.storyboard!.instantiateViewControllerWithIdentifier(“XYZIdentifier”) as! XYZViewController
viewController.providesPresentationContextTransitionStyle = true
viewController.definesPresentationContext = true
viewController.modalPresentationStyle=UIModalPresentationStyle.OverCurrentContext
self.presentViewController(viewController, animated: true, completion: nil)
For Swift 4 :
let viewController = self.storyboard!.instantiateViewController(withIdentifier: "XYZIdentifier") as! XYZViewController
viewController.providesPresentationContextTransitionStyle = true
viewController.definesPresentationContext = true
viewController.modalPresentationStyle = .overCurrentContext
self.present(viewController, animated: true, completion: nil)
And the backgroundcolor of your presented viewController should be clearColor.