iOS 判断设备型号、屏幕尺寸、系统版本、设备朝向

//判断设备型号
#define UI_IS_LANDSCAPE         ([UIDevice currentDevice].orientation == UIDeviceOrientationLandscapeLeft || [UIDevice currentDevice].orientation == UIDeviceOrientationLandscapeRight)
#define UI_IS_IPAD              ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad)
#define UI_IS_IPHONE            ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone)
#define UI_IS_IPHONE4           (UI_IS_IPHONE && [[UIScreen mainScreen] bounds].size.height < 568.0)
#define UI_IS_IPHONE5           (UI_IS_IPHONE && [[UIScreen mainScreen] bounds].size.height == 568.0)
#define UI_IS_IPHONE6           (UI_IS_IPHONE && [[UIScreen mainScreen] bounds].size.height == 667.0)
#define UI_IS_IPHONE6PLUS       (UI_IS_IPHONE && [[UIScreen mainScreen] bounds].size.height == 736.0 || [[UIScreen mainScreen] bounds].size.width == 736.0) // Both orientations
#define UI_IS_IOS8_AND_HIGHER   ([[UIDevice currentDevice].systemVersion floatValue] >= 8.0)