iPhone 4S :
A low voltage Apple A5 CPU (it won’t be the same as the iPad 2 chip, clock for clock).
Updated front and back camera sensors. FaceTime HD in the front, 8-megapixel 1080p HD video recording in the back.
Multiband 3G Qualcomm chipset — North American & International GSM/UMTS/HSPA bands for AT&T and Global carriers, North American CDMA & International GSM/UMTS/HSPA bands for Verizon and Sprint.
NFC support.
Metal or “premium” plastic on the back case.
iPhone 5 :
Faster CPU.
Larger 4-inch screen, similar to LG’s NOVA display but with a higher resolution.
1GB of RAM.
Slightly larger design overall, but thinner and with a larger battery.
32GB of storage.
iPhone 5 exclusive software and APIs (Assistant).
DedicatedAssistantbutton, possiblyintegratedwith the new home button, “think gestures or a two-stage button like a camera shutter key).