要确定你的应用是否支持iPhone 5 Retina，请使用以下方法: (这可以更健壮地返回显示类型，4S视网膜等，但正如下面所写的，如果iPhone支持iOS5视网膜，它只返回YES或NO)

在一个普通的“。h”文件中添加:

BOOL IS_IPHONE5_RETINA(void);

在一个共同的”。M”文件添加:

BOOL IS_IPHONE5_RETINA(void) {
    BOOL isiPhone5Retina = NO;
    if(UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone) {
        if ([UIScreen mainScreen].scale == 2.0f) {
            CGSize result = [[UIScreen mainScreen] bounds].size;
            CGFloat scale = [UIScreen mainScreen].scale;
            result = CGSizeMake(result.width * scale, result.height * scale);

            if(result.height == 960){
                //NSLog(@"iPhone 4, 4s Retina Resolution");
            }
            if(result.height == 1136){
                //NSLog(@"iPhone 5 Resolution");
                isiPhone5Retina = YES;
            }
        } else {
            //NSLog(@"iPhone Standard Resolution");
        }
    }
    return isiPhone5Retina;
}

使用视图的自动布局功能。它将自动调整到所有分辨率。

为控制器名称后缀为~iphone或~ipad的控制器创建两个xib。在编译时，Xcode将根据设备取正确的xib。

使用大小类，如果你想为iPhone和iPad创建一个单独的xib，如果视图足够简单，可以移植到iPhone和iPad。

这是一个真正的通用代码，你可以创建3个不同的故事板:

设置你的项目通用模式，用iPhone5 storyboard设置你的主故事iPhone，用ipad target storyboard设置ipad main，现在为iPhone添加新的storyboard target，并修改iPhone 4s或更少的分辨率，现在实现你的appdelegate。m

iPhone4/4s (3/ 3g是一样的)一个iPhone5，并使项目通用，与一个新的Storyboard目标为iPad，现在在AppDelegate。在didFinishLaunching下添加以下代码:

    if(UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone){
        UIStoryboard *storyBoard;

        CGSize result = [[UIScreen mainScreen] bounds].size;
        CGFloat scale = [UIScreen mainScreen].scale;
        result = CGSizeMake(result.width *scale, result.height *scale);

//----------------HERE WE SETUP FOR IPHONE4/4s/iPod----------------------

        if(result.height == 960){
            storyBoard = [UIStoryboard storyboardWithName:@"iPhone4_Storyboard" bundle:nil];
            UIViewController *initViewController = [storyBoard instantiateInitialViewController];
            [self.window setRootViewController:initViewController];
        }

//----------------HERE WE SETUP FOR IPHONE3/3s/iPod----------------------

        if(result.height == 480){
            storyBoard = [UIStoryboard storyboardWithName:@"iPhone4_Storyboard" bundle:nil];
            UIViewController *initViewController = [storyBoard instantiateInitialViewController];
            [self.window setRootViewController:initViewController];
        }
    }

        return YES;
 }

所以你已经为iPhone 3/ 3g /4/4s/5所有一代的iPod和所有类型的iPad创建了一个通用应用程序

记住将所有IMG与myImage.png和myImage@2x.png集成

在这里你可以找到一个很好的教程(MonoTouch，但你也可以使用非MonoTouch项目的信息): http://redth.info/get-your-monotouch-apps-ready-for-iphone-5-ios-6-today/

为你的splash/default屏幕创建一个新图像(640 x 1136像素)，名称为Default-568h@2x.png 在iOS模拟器中，转到硬件->设备菜单，并选择“iPhone(视网膜4英寸)” 创建其他图像，例如背景图像 检测iPhone 5加载你的新图像:

public static bool IsTall
{
    get {
        return UIDevice.currentDevice.userInterfaceIdiom
                    == UIUserInterfaceIdiomPhone
                && UIScreen.mainScreen.bounds.size.height
                    * UIScreen.mainScreen.scale >= 1136;
    }
}

private static string tallMagic = "-568h@2x";
public static UIImage FromBundle16x9(string path)
{
    //adopt the -568h@2x naming convention
    if(IsTall())
    {
        var imagePath = Path.GetDirectoryName(path.ToString());
        var imageFile = Path.GetFileNameWithoutExtension(path.ToString());
        var imageExt = Path.GetExtension(path.ToString());
        imageFile = imageFile + tallMagic + imageExt;
        return UIImage.FromFile(Path.Combine(imagePath,imageFile));
    }
    else
    {
        return UIImage.FromBundle(path.ToString());
    }
}

According to me the best way of dealing with such problems and avoiding couple of condition required for checking the the height of device, is using the relative frame for views or any UI element which you are adding to you view for example: if you are adding some UI element which you want should at the bottom of view or just above tab bar then you should take the y origin with respect to your view's height or with respect to tab bar (if present) and we have auto resizing property as well. I hope this will work for you

I never faced such an issue with any device as I've had one codebase for all, without any hardcoded values. What I do is to have the maximum sized image as resource instead of one for each device. For example, I would have one for retina display and show it as aspect fit so it will be views as is on every device. Coming to deciding the frame of button, for instance, at run time. For this I use the % value of the patent view, example , if I want the width to be half of parent view take 50 % of parent and same applies for height and center.

有了这个，我甚至不需要xib。