I have set the three image for the @2x @Retina 4 and @3x.
When i run t
In iPhone 6 you will get the image which is of @2x In iPhone 5 and 5s you will get the image of Retina 4 @2x.
Check this example image I have set here.
Result in iPhone 5
Result in iPhone 6
but in iPhone 4 and iPhone 6 you will get same image. For this time you have to code for different devices. Because apple does not provide the document for it. by the time if I got something new then I will post here.
Thanks!