iPhone 5S would have gone into production at Foxconn, the launch would be scheduled for the summer of 2013
Following the rumors on the internal structure of the iPhone 5S terminal, today we learn that Foxconn had already begun to produce terminal in their own factories, but in moderation cuantities now. iPhone 5S would be assembled on production lines that iPhone 5 is manufactured, meaning that the external structure of the device is unchanged, as you already expected. Foxconn is ready to increase over the next production in order to allow Apple to launch its terminal in June/July or August, according to rumors published to date.
iPhone 5S is expected to maintain the design and the screen of the iPhone 5 terminal, but would have an A7 chip with a better processor, manufactured using a 28nm manufacturing process, would have a better camera equipped with Smart Flash and could have a fingerprint reader and a better battery. Yet no one knows what new features will include iOS 7, but if iPhone 5S will be released in the summer, then in the coming months we will have iOS 7 available in beta state.