If you were watching the keynote on September 12 this month, you'd be quite bored by the number of times Phil Schiller used the term "A11 Bionic" while describing every feature in all the iPhones. We could've played a drinking game, where every time Phil said the word "A11 Bionic", we would take a shot, and I'm telling you, we'd be wasted before the keynote was even finished.
Now, at the time I, like most of you could not understand the performance and the capability of the Apple's new A11 Bionic chip and why it was stressed in describing almost every feature of the new iPhones. Turns out the performance of this hexacore processor is way beyond than the processor that used to sit on top of this list. This was measured by Geekbench4 scores for the computation, and the Apple A11 Bionic performed outrageously well for single core performance and its multi-core performance.
The A11 Bionic chip is essentially a 64-bit hexacore processor with two high-performance cores(which is 25% faster than Apple's A10 chip) and four high-efficiency cores (which is 70% faster than Apple's A10 chip). The major advancement over its predecessor is that A11 can run both types of its cores simultaneously to get this beast of a performance. Above all that, the processor is optimized to such lengths that it achieves A10's performance at half the power.
Besides these, this A11 Bionic chip also powers Apple's A11 Neural Engine, does pixel processing in real time, houses an Apple-designed GPU which is 30% faster than the one in A10's chip. The 2nd generation Apple designed performance controller is 70% faster in handling multithreaded workloads than its predecessor. I'm not sure about innovation in terms of UI and other features, but Apple really killed it here in terms of the performance that it delivered.
You can also read how iPhone cameras have fared out in DxOMark tests.