please see the attached image which shows how the iPhone displays my content (left), compared with how the Unity player displays everything (right). Note how it's squahsed in X when on the iPhone. Images/buttons are sprites, using SpriteManager. Why would this happen?
At last I figured it out (lots of head scratching and hair pulling later)
Camera.ResetAspect();
I don't believe I was ever actually setting aspect, but rather just setting orthographic size, but either way, ResetAspect() is your friend in this case! :)