Apple announced the anticipated successor to the iPhone 5, the iPhone 5s, along with the budget oriented iPhone 5c during its September 10 event. As the "5s" designation indicates, Apple's new iPhone brings incremental improvements to its predecessor.
Apple has added two very interesting features to the iPhone 5s: a dual-LED flash, where each LED has a different color temperature, and software-based measurements tell with what intensity should each of the LEDs light up in order to create a natural-looking lighting. Also, while the rear camera is still 8 MP, in an age where 13 MP cameras are a must for a flagship, and there are even 41 MP bearing smartphones. Apple is compensating for the unchanged image resolution by increasing pixel size, making the optical sensor 15% larger. HTC used the very same strategy with the HTC One. Other details about the camera include an unsurprising 1080p video capture capability and one cool new feature: An option for 120fps 720p video recording, which then gets played back at 30fps to create a nice Slow Motion effect.
The other cool new feature of the iPhone 5s is the Touch ID fingerprint sensor. Basically, the iconic Home button has been overhauled, and now consists of a sapphire crystal layer on the top, beneath which is a fingerprint scanner, so that you no longer need to protect your iPhone with a password or PIN; just put your thumb over the Home button and, given that you've registered your own fingerprints on the phone, voila, your iPhone unlocks. That is what I consider to be the most innovative feature of the iPhone 5s.
Changes aside, the iPhone 5s still has the same Gorilla Glass-coated 4-inch 1136 x 640 (326ppi) IPS display from the iPhone 5, which, by today's standards, is far too small for a flagship smartphone.
Under the hood, the iPhone 5s also packs some notable improvements over its predecessor. Battery capacity is slightly increased, but what takes the spotlight is the new Apple A7 chip. One rather remarkable accomplishment is that the A7 is the first smartphone processor based on the ARMv8 ISA. This means that the A7's CPU is a 64-bit CPU; a first in any mobile device. SoCs based on ARMv8 were only supposed to start appearing in the next year or two, but Apple has beaten everyone to it. A 64-bit CPU doesn't sound like it'll be very useful on a mobile device (Apple won't need to make an iPhone with more than 4 GB of RAM in years, probably), and the performance gains it brings are minimal for most smartphone usage scenarios, but it does pave the way for the future of iPhone. Other than the architecture, Apple didn't specify any details about the A7's CPU (what a surprise). They only said that it's performance is double than the iPhone 5's A6 processor. That should roughly put it on par with the Snapdragon 600, but significantly behind the Snapdragon 800 and the Exynos 5 Octa. On the GPU side, Apple went on to say that the GPU is also twice as powerful as the iPhone 5's and that it supports OpenGL ES 3.0. The support for OpenGL ES 3.0 can only mean that Apple is moving away from the PowerVR SGXMP architecture it's been using since 2011, and possibly adopting ImgTech's new PowerVR series, codenamed Rogue.
Last but not least, the iPhone 5s will be shipping with the overhauled iOS 7 and is expected to become available this month with the usual 16, 32 and 64 GB storage options.