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Same 4" screen & design.

- LED Notification in the front
- Quad-core A7 chip?
- 10MP Camera
- Battery life improved
- New iOS including features like or similar to SBSettings.
- NFC
- New SIRI options
- No 128GB iPhone model yet

You should separate your iPhone 5S features from your iOS7 features.
 
Assuming that the 5S updates only the internals:

Faster CPU/GPU
More RAM
128GB Flash availability

Minor external changes:

More color options
Stainless steel option instead of anodized aluminum

These are NOT predictions. They are a kind of wish list that I don't expect will happen.
 
iPhone 5s
Hardware:

Wireless Charging
Carbon Fiber Back Plate (Real Carbon Fiber)
Custom orders for color schemes.
Notification light (I prefer the Home Button’s square line as the LED notification becon)

Software:

Apple Widgets (Look up Evernote’s widget on someone’s Android device)
Unlock the app icons so we can adjust them to where we want to put them!
NFC (It’s nice to go up to the cash register and wave the phone to pay)
 
Retro Edition with the beige plastic shell of the Apple //e or first Mac computer.

Maybe only monochrome black and green LCD colors or black and white display too.
 
I'm betting a name change to just "iPhone" or "The New iPhone" 5 is a nice number to go to... but doing the iPad route seems like a much smarter idea for future iterations... that way there is no expectations of the phone to be leaps and bounds "better"
 
I would love a fingerprint reader that actually works. I'm sure we'll see a slightly faster processor and likely a little better camera. I don't see storage sizes increasing much but faster speed storage with USB3/Thunderbolt adaptors would be very welcome. If Apple wasn't so greedy 32GB would be standard. The difference between 16 and 32 is less than $10. At the least make it a $50 upgrade instead of $100. 10x mark-up is just screwing your customers.
 
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