Part of the price difference will be the cost of shipping and handling, customer service, warranties, etc, but I think it is reasonable to claim that at least $200 will remain after factoring in those. People do buy these phones, so there must be some $200 of value in an iPhone that is not attributable to its hardware. People will have different views on where that value is, but IMO, it is not unreasonable to assume half of it is in the iPhone UI.
I cannot find logic that $30 is reasonable, but I cannot find logic that shows $30 is unreasonable, either.
Here is some food for thought: iSuppli claims the iPhone 4S contains $188 of materials (http://www.isuppli.com/Teardowns/News/Pages/iPhone-4S-Carrie...). That "$188 BOM" 16GB phone sells for $649 on the Apple Store.
Part of the price difference will be the cost of shipping and handling, customer service, warranties, etc, but I think it is reasonable to claim that at least $200 will remain after factoring in those. People do buy these phones, so there must be some $200 of value in an iPhone that is not attributable to its hardware. People will have different views on where that value is, but IMO, it is not unreasonable to assume half of it is in the iPhone UI.
Based on that logic, $30 seems not unreasonable.