Here is Anandtech's review of the fruit 5s.
I am posting it here for an understanding of 64 bit computing, since Anand gives a very detailed explanation of CPU design and good comparisons.
http://www.anandtech.com/show/7335/the-iphone-5s-review..... NVIDIA and Samsung, up to this point, have gone the processor license route. They take ARM designed cores (e.g. Cortex A9, Cortex A15, Cortex A7) and integrate them into custom SoCs. In NVIDIA’s case the CPU cores are paired with NVIDIA’s own GPU, while Samsung licenses GPU designs from ARM and Imagination Technologies. Apple previously leveraged its ARM processor license as well. Until last year’s A6 SoC, all Apple SoCs leveraged CPU cores designed by and licensed from ARM.
With the A6 SoC however, Apple joined the ranks of Qualcomm with leveraging an ARM architecture license. At the heart of the A6 were a pair of Apple designed CPU cores that implemented the ARMv7-A ISA. I came to know these cores by their leaked codename: Swift.
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I always thought the transition from 2 to 4 cores happened quicker in mobile than I had expected. Thankfully there are some well threaded apps that have been able to take advantage of more than two cores and power gating keeps the negative impact of the additional cores down to a minimum. As we saw in our Moto X review however, two faster cores are still better for most uses than four cores running at lower frequencies. NVIDIA forced everyone’s hand in moving to 4 cores earlier than they would’ve liked, and now you pretty much can’t get away with shipping anything less than that in an Android handset. Even Motorola felt necessary to obfuscate core count with its X8 mobile computing system. Markets like China seem to also demand more cores over better ones, which is why we see such a proliferation of quad-core Cortex A5/A7 designs. Apple has traditionally been sensible in this regard, even dating back to core count decisions in its Macs. I remembering reviewing an old iMac and pitting it against a Dell XPS One at the time. This was in the pre-power gating/turbo days. Dell went the route of more cores, while Apple chose for fewer, faster ones. It also put the CPU savings into a better GPU. You can guess which system ended out ahead.......
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Extremely detailed discussions and benchmarks.