Scroll view setup with basic view controller

ViewController.m

- (void)viewDidLoad
{
    [super viewDidLoad];

    // Get screen size (e.g. iPhone 4 or 5)
    CGRect screenSize = [[UIScreen mainScreen] bounds];
    
    // Sets dimensions for the root view and scroll view
    [self.view setFrame:CGRectMake(0.0, 0.0, screenSize.size.width, screenSize.size.height)];
    [scrollView setFrame:CGRectMake(0.0, 0.0, screenSize.size.width, screenSize.size.height)];
    
    // Adds the scroll view as a child of the root view
    [self.view addSubview:scrollView];
    
    // Adds the main view as a child of the scroll view
    [scrollView addSubview:mainView];
    
    // Sets scrollable area to be the same dimensions as the main view
    [scrollView setContentSize:mainView.frame.size];
    
    // Adds a bottom margin to the scroll view so the main view doesn't
    // abruptly end at the bottom edge
    [scrollView setContentInset:UIEdgeInsetsMake(0.0, 0.0, 64.0, 0.0)];
}