Original Link: http://www.anandtech.com/show/6292/iphone-5-a6-not-a15-custom-core

Anand La Shimpi:

The A6 is the first Apple SoC to use its own ARMv7 based processor design. The CPU core(s) aren’t based on a vanilla A9 or A15 design from ARM IP, but instead are something of Apple’s own creation.

The A6 is only twice as fast as last year’s A5.