The A8 processor in the iPhone 6 will have a clock speed of up to 2.0 GHz or even more. It is a major advancement to the A7 1.3GHz processor in the iPhone 5s. However, it will still be a 64-bit dual-core processor, so with two processor cores, made with a 20-nanometre technology.
According to the latest rumors will the A8 processor continue to adopt the existing 64-bit dual-core architecture with its focus on power efficiency and hence yield only a marginal boost in CPU speeds.
But the questions is, is it good enough, because the current A7 processor performs often better than the quad and octacore processors in a lot Android phones.
Apple A8 ProcessorThe Apple A8 processor which will probably be made by TSMC and Samsung - although Samsung is still a bit uncertain. Earlier were rumors that Taiwan Semiconductor Manufacturing (TSMC), going to do the whole production of the A8 processor. Apple wants to be less dependent of Samsung.
Apple's A9 processor will probably produced by TSMC and Samsung and will appear in 2015. But Samsung will only get 30 to 40 percent of the production. The rest is for TSMC.
Check also: New iPhone Air concept, and 3D games for iPhone Air (6) make use of realistic reflections.