title: How to change size of UIImageView on iphone5 & iphone6?
body: <p>I have an image to display in my app.
  I want to set the size of the image on iPhone6 to 169pt &amp; on iPhone5 set it 120pt.
  I know there is a size class on iOS8. But how can I set different sizes for different iPhones on it. 
  I can only distinguish between iPad &amp; iphone portrait/landscape in size classes &amp; can not distinguish iPhone 5 from iPhone6</p>