Snippet of code that put's an image in the background of a UIImageView and scales it appropriately to the main window dimentions.

bg-image-ui-view

    UIScreen* mainScreen = [UIScreen mainScreen];
    
    CGRect frame = mainScreen.bounds;
    MyUIView* view = [[MyUIView alloc] initWithFrame:frame];

    UIImage* background = [UIImage imageNamed:@"[email protected]"];
    UIImageView* bgView = [[UIImageView alloc] initWithImage:background];
    bgView.frame = frame;