Interface orientation in iOS 6.0

Deprecated method in iOS 5:

// Override to allow orientations other than the default portrait orientation.
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation 
{
    // Return YES for supported orientations
    return (interfaceOrientation == UIInterfaceOrientationLandscapeRight);
}

Replacement in iOS 6 and equivalent of this deprecated iOS 5 method above:

- (BOOL) shouldAutorotate
{
    return YES;
}

-(NSUInteger)supportedInterfaceOrientations
{
    return UIInterfaceOrientationMaskLandscapeRight;
}

Hope this helps.

---

[edit #1: Added my UIViewController which successfully starts in Portrait mode in XCode 4.5 on iPhone 6.0 Simulator]

#import "FirstViewController.h"

@interface FirstViewController ()

@end

@implementation FirstViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];

    if (self)
    {
        // Custom initialization
    }

    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
}

-(BOOL)shouldAutorotate
{
    return NO;
}

-(NSUInteger)supportedInterfaceOrientations
{
    return UIInterfaceOrientationMaskAll;
}

- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation
{
    return UIInterfaceOrientationMaskPortrait;
}

[#edit 2: Sample code from landscape only application which supports iOS 5 and iOS 6]

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {

    return (interfaceOrientation == UIInterfaceOrientationLandscapeRight) || (interfaceOrientation == UIInterfaceOrientationLandscapeLeft);
}

- (BOOL)shouldAutorotate {

    return YES;
}

- (NSUInteger)supportedInterfaceOrientations {

    return UIInterfaceOrientationMaskLandscape;
}

- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation {

    return UIInterfaceOrientationLandscapeLeft;
}