Apple has just announced the new iPhone 5S smartphone, and along with it a 64-bit processor, which they have promoted as a big feature of the new iPhone. But is it, really?
We were already expecting to see 64-bit processors next year, but it seems Apple pulled ahead of everyone with this. How did they do it? My guess is that unlike everyone else, who is switching both the architecture (ARMv8) and the CPU core design, Apple is only doing one of those – switching to the ARMv8 architecture, while using the same Swift core as last year, but with a higher clock speed. This is probably why we saw rumors earlier that the chip is only going to be 31 percent faster, which would put it somewhere around 1.5-1.6 Ghz (dual core).
The reason why I initially didn't think Apple would do a 64-bit processor this year, was because I knew it would take them a little longer to change the CPU design, too, and Apple has just launched this Swift core last year. These chips have a 2 year generation, usually, and Apple was only halfway there. But it seems they created a shortcut by using the same CPU core, but they must've managed to build it again on top of the ARMv8 architecture. The advantage is that they are moving faster than everyone else to 64-bit, while the disadvantage is that this chip won't be as fast as it would've been if they continued with ARMv7.
But what does 64-bit give them anyway? Not much right now, other than bragging rights. This is especially true for the iPhone and iPads, which usually tend to have lower amounts of RAM than the competition. In fact, the new iPhone will most likely use only 1 GB of RAM again, if not, 2 GB at most. I'm not really expecting them to put 4 GB of RAM in the iPhone or iPad at least until 2015, while we should see some Android tablets and phones with 4 GB of RAM next year, along with 64-bit processors.
I think Apple just wants to lay the groundwork for future updates, and make it possible for them to go 64-bit-only for iOS earlier, just like they've already done for the Mac OS, especially since they tend to offer 3 year upgrades for their phones.
This move also proves that Apple is very committed to making its own ARM CPU and having control of their processors like that, and that they will never even consider using Intel chips in their iOS devices. If anything, they might start switching Mac OS to these ARM chips, too, now that they are 64-bit, although if they'll even do that, it's probably going to take a year or two more.
But as I mentioned, in practical terms, this doesn't mean much in terms of performance, so I wouldn't stress too much about not having 64-bit processors on Android devices yet. ARM seems to have planned the launch of the ARMv8 architecture very well, because it's going to arrive just in time when our devices will be getting 4GB of RAM (next year).