The A6, unlike its predecessors the A5 and A4, isn’t simply a rebranded ARM design with minor tweaks. Instead, as Anand Shimpi of AnandTech discovered, it’s Apple’s own creation, based on an ARM blueprint — which it also licensed in addition to specific generic processors — but bearing much more of Apple’s own direct input. In other words, Apple is finally emerging as a chipmaker in its own right, and this could have a huge impact on device performance and consumer-facing features in its smartphones and tablets going forward.
Since Apple can now build its own chips, it will focus on the most important thing: power saving. ARM was probably trying to make the best mobile chips anyway but Apple knows battery life is the single most important aspect of the iPhone.