The iPhone 5S is more than just a "Better iPhone 5" and by a long shot. This is, in fact, the first time Apple has ever released a "Secondary" iPhone that warranted a full version jump marketing wise. IE iPhone 6 is the more proper name for the amount of change inside the iPhone 5S.
Lets look at the why.
The A7 SoC is the first full 64 bit CPU in the history of cell phones. It is the only dual core CPU that can currently beat every quad core based Android phone on the market. Let that sink in for a bit......
FIRST to 64 bits....
Little more.....
FASTER than all quad core Android cell phones currently made....
Ok. That's enough sinking in.
This also means the iOS will be the first mobile OS to have truly NATIVE 64 bits apps. Both from Apple and 3rd party developers. Anyone coming from the iPhone 4S or older is going to be in for a big shock when they upgrade to the iPhone 5S. It is going to be that big of a jump in speed and fluidity. iPhone 5 users will also notice a difference. Especially in native app performance. Third party apps will need time to recompile under the new XCode and deploy to see big jumps there.
iOS 7 and the new security instruction sets on the A7 will make encryption and secure purchases an after thought. Something that is there working at full speed all the time and the user doesn't have to do or wait for anything.
The fingerprint scanner should make locking and unlocking an iPhone second nature instead of an inconvenience.
The new stabilization software, thanks to the power of the A7, for the camera should make low light pictures look much better than any previous iPhone or even Android phones. Well save for the HTC One once it gets it software patch.
Folks, the iPhone 5S is a game changer. The ground work laid with this iPhone will allow for huge advancements in design and coding for all future iOS devices. It's a shame it will take about a year, in my opinion, before the industry and users realize just how ground breaking this new iPhone is.
And anyone buying the iPhone 5C is really missing out. They should have spent the extra $100 and got the 5S.