There are only a few major differences between the iPhone 5S and iPhone 5C, but performance is one of them.
The iPhone 5S features Apple's 64bit A7 chip, which is paired with the firm's M7 coprocessor for more accurate movement detection. The iPhone 5C, on the other hand, features Apple's previous generation A6 processor that made its debut in the iPhone 5.
While there are no major performance differences between the two in real-world testing, the iPhone 5S is the more powerful of the two compared to its cheaper sibling in gaming, opening apps, and loading webpages. We also found everything was a little bit smoother on the iPhone 5S, with the iPhone 5C stuttering occasionally.
Winner: iPhone 5S
Both the iPhone 5S and iPhone 5C run Apple's latest iOS 7 mobile operating system.
Of course, the software remains nearly identical on both devices. There are a few slight differences, with the iPhone 5S boasting the ability to buy apps, and of course unlock the device using the built-in Touch ID sensor. The iPhone 5S camera app also comes with a built-in slow-motion video recording mode, a feature that's missing on the cheaper iPhone 5C.
As we mentioned, iOS 7 is also slightly smoother on the iPhone 5C, with apps opening a fraction quicker, webpages loading more smoothly, and gameplay being more impressive.
Beyond that, however, you'll find the same, minimalist iOS 7 user interface and features on both the iPhone 5S and iPhone 5C. Although Apple's latest mobile operating system received a fair bit of criticism at launch and we still have our gripes with the reworked user interface, we have warmed to iOS 7. The new user interface feels fresh, and new features such as the Control Center and the redesigned Safari web browser are welcome.
Winner: iPhone 5S
Next: Cameras, battery and storage, price.