Singleton Viewcontroller Storyboard

static id s_singleton = nil;

+ (id) alloc {

    if(s_singleton != nil)

        return s_singleton;

    return [super alloc];

}

- (id) initWithCoder:(NSCoder *)aDecoder {

    if(s_singleton != nil)

        return s_singleton;

    self = [super initWithCoder:aDecoder];

    if(self) {

        s_singleton = self;

    }

    return self;

}