While the A9 chip seems to keep the iPhone 6S and 6S Plus running smoothly, Apple's iPhone 7 is expected to include more complex technology. ARM and TSMC have announced a 10nm FinFET chip which should increase power and efficiency even more. While the chip has yet to see a date from ARM, TSMC is expected to produce 10nm silicon in April or May 2016.
The question here is whether the technology will be completed and ready for the iPhone 7. The new chip would include an Artemis CPU core, which consists of a 4-core cluster. The technology has been said to achieve a 11-12% performance boost and 30% power usage reduction. This is a chip we will definitely want to see an a future iPhone or iPad.
Source: BGR