How to check in which position (landscape or portrait) is the iPhone now?

Question

I have an app with a tab bar, and nav controllers in each tab. When user shakes the device, a UIImageView appears as a child view in the nav controller. But the

Answer 1

As beno said, this seems a better answer if you are detecting orientation early in your View. I couldn't get the approved answer to return a result early in my setup but this works wonderfully.

if (UIDeviceOrientationIsPortrait(self.interfaceOrientation)){
//DO Portrait
}else{
//DO Landscape
}