Motherboard of iPhone 5S? from Japanese blog, MOUMANTAI
MOUMANTAI uploaded several photos of iPhone 5S's printed circuit board.
Those photos show the motherboard may be very similar to one of iPone 5 (iFixit), but layout of screw-holes is differ from current one.
According to that photo, size of MPU seems to be same with iPhone 5. And, the number of chips seems to be smaller caused custom controller development proceeded in Apple.