Do I need to buy an iPhone 5 to submit the app for approval or can I use my iPhone 4S to do it?
Did you test your app on the iPhone 4-inch simulator yet?
Yes and on an iPhone 4S, but do I need to test it on iPhone 5 or send screen shots from iPhone 5 for it to be approved?
There is no 'requirement' other than the reliable practice of testing on devices you intend to support so that your users don't do that for you
Screenshots can be obatined using the iPhone 4-inch simulator menus.
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