Rounded Corners in iOS Sim But Not iPhone
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I'm really new to iOS coding, and I have a UI question. 

In the simulator, my app has rounded corners like this: http://i.imgur.com/cc8eM.png

I like that!

But on the actual iPhone, they look like this: http://i.imgur.com/hyVKu.png

How can I make the iPhone version have those rounded corners? Thanks!