"The company’s largest and most complex effort remains the iPhone application processor. The 64-bit A10 Fusion in the iPhone 7 and 7 Plus packs 3.3 billion transistors.

The SoC adopts ARM’s Big.little approach, using two high performance cores running 40% faster and two high efficiency cores at one-fifth the power consumption of the A9 SoC in the iPhone 6. It also sports a six-core GPU that’s 50% faster than graphics in the A9.

“It’s the most powerful chip in a smartphone,” said Apple Vice President of marketing Phil Schiller, although companies including Mediatek and Samsung are shipping apps processors with eight or more cores.

Apple provided few details on its chip-level work. It left gaping holes about whether all the A10 cores were custom or some were sourced from ARM or others, what process the chips were made in and what data rates they hit.

The company was most forthcoming about its success in greater silicon efficiency. As a result the iPhone7 on average delivers as much as two hours longer battery life than the iPhone 6, although on the dual-camera iPhone 7 Plus the extra life is trimmed that to one hour."

http://www.eetimes.com/document.asp?doc_id=1330418