Why Apple went 64-bit with the iPhone 5s

Why Apple went 64-bit with the iPhone 5s

Summary: The reasons why Apple put a 64-bit processor inside the iPhone 5s goes way beyond hype. While the applications for it might be limited right now, Apple is paving the way for improvements that we'll see trickle into the iPhone over the next few years.

A7 inside the iPhone 5s
(Source: Apple)

One of the flagship features of Apple's new iPhone 5s is that it has at its heart the 64-bit A7 chip. But why did Apple feel the need to bump the iPhone's processor up from 32-bits in the first place?

It's a first

Apple like bragging about being first.

It looks and sounds good

Come on, making the leap from a 32-bit processor to a 64-bit processor looks and sounds good. When dealing with consumers, throwing in some numbers that are bigger than what the competition can manage – 1 billion transistors, 64-bit – helps sales.

On top of that, Apple threw around the phrase 'desktop-class architecture' during the unveiling of the iPhone 5s, which also sounds pretty cool, don't you think?

Android isn't ready for 64-bit

Apple has scored a win here over Android handset makers. The 64-bit chips for Android devices aren't ready, and neither is Android itself. It is likely that Android 5.0 will be the first version to fully utilize the new ARMv8 architecture.

For now, this gives Apple a clear lead over the competition, and the gap is unlikely to the closed until 2014 at the earliest.

The move allows for more RAM

The iPhone 5 is kitted out with 1GB of RAM, but a shift from a 32-bit processor to a 64-bit part paves the way for iPhones – and for that matter, the iPad or even Apple TV, where more RAM could open the way for 4K – to be fitted out with 4GB+ of RAM down the line.

Since Apple doesn't divulge how much RAM is baked into iPhones, we'll have to wait for the teardown to find out the exact figure, but despite the shift to a 64-bit processor, I'm not expecting it to have 4GB, but there will come a day when it is needed.

Apple is now ready for that day.

Unifying the iOS/OS X app codebase

Apple openly acknowledges that moving iOS up to 64-bit brings iOS and OS X apps much closer. Take this line from Apple's 64-bit iOS 7 documentation:

The architecture for 64-bit apps on iOS is almost identical to the architecture for OS X apps, making it easy to create a common code base that runs in both operating systems.

This could be huge.

64-bit CPUs are better suited to some heavy computational lifting tasks

There are some iPhone 5s features that could benefit from having access to a 64-bit processor. The camera that can pick the best picture from a series of shots and allow you to fire off slo-mo video at 120 frames per second is one. Image processing is demanding, and the headroom offered by the A7 processor could lessen the workload.

Same goes for that fingerprint reader. If Apple is using heavyweight crypto behind that scanner, then this too would benefit from a 64-bit processor.

Puts pressure on Intel

Currently, CPUs for Mac hardware is supplied by Intel, but the A7 processor, with its billion transistors and 64-bit architecture, sends a clear message that Apple is serious about developing its own processors.

While I don't see Apple shifting away from Intel any time soon, the fact that the company is now a big player in the processor market helps even the playing field between it and Intel, and puts it in a stronger position when negotiating.

Bottom line

The bottom line is that there's a lot more to the iPhone switching to a 64-bit processor than hype. While the applications for it might be limited right now, Apple is paving the way for improvements that we'll see trickle into the iPhone over the next few years.

Topics: Mobility, Apple, iPhone, Processors

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  • Hmmmmm

    Google is likely launching KitKat before the end of the year (along with a Nexus 10 update). Samsung (who backed Apple's new chip) has already announced they'll be releasing their on 64-bit processor before the end of the year (now, it might not appear in an actual device before then), so I wouldn't bet on this being a "lead" for Apple for long.

    That being said, 32-bit processors can support (a max of) 4 GB of RAM, so your argument about more memory is kind of silly. Why doesn't the current iPhone sport at least 2 GB (which even mid-range Android handsets come with)?

    I'm sorry, but, at this point, the 64-bit processor is nothing but a marketing ploy by Apple. I am excited they are doing it, because it means a brighter future for mobile processing--absolutely. We need the 64-bit architecture.

    But it's not going to give them an immediate edge. Apps likely won't start truly utilizing the 64-it architecture until late 2014 anyway. That goes for all the platforms that adopt it (If you don't think MS is going to follow-up with their own 64-bit processor, you're delusional).

    To sum up: Yes, this is a step forward, but no, it doesn't give the iPhone any kind of CURRENT edge over existing 32-bit architecture. There simply isn't anything out there that's going to utilize it, and the iPhone doesn't have enough memory to make it truly "revolutionary." (See what I did there?) But, it absolutely IS a step in the right direction!
    • So...to sum up...

      You have not even a remote clue as to what advantages 64bit capability has given Apple, iOS or the optimised apps?
      • You can tell how far Apple hit the ball by the yelps

        and squeals of the Android/MS crowd. And judging by the wholesale gnashing of teeth going on right now, this 64-bit CPU is a big deal.
        • Ha Ha, good one

          the yelps you're hearing are hoots and catcalls. Put me in the confused crowd who cannot yet see one advantage to a 64 big processor on a smart phone. Let me know when your IPHONE 8 somes with 16G of ram.
          • No, not even close...

            The fact Samsung felt they had to claim they were going to be releasing a 64 bit processor tells us two things:

            • Firstly, Samsung had no clue Apple were going to do this.

            • Secondly, it means that Samsung aren't supplying the processor.

            Apple just shafted Samsung by taking away all that processor fab business. No wonder they felt they had to say something. If they'd had kept their mouth shut we could have thought anything. But by speaking we know they're worried.
          • It has already been stated numerous times

            the advantages a 64-bit CPU provides beyond more memory support. Your only excuse for ignorance now is willful denial of reality.
      • Agree; 64-bit makes all massive integer calculations such as, say, ...

        ... decompression up to half faster (at the same clock) in 64-bit versus 32-bit -- simply because the length of register is 8 bytes, not 4 bytes as before. Instructions move data much faster because of that.

        Additionally, ARMv8 has twice more registers, which in another way how calculations are faster right away even at the same clock speeds as 32-bit version.
    • RE: Hmmmmm

      So let's just stay with 32-bit forever. There are a multitude of reasons why 64-bit architecture makes sense now, and to argue against it is really pointless. They're going 64-bit.

      To mention Android really doesn't make sense either, unless you want to play the marketing game - Apple devices don't run Android and before you say "but that's their competition!", it doesn't matter.

      Apple is going to have a 64-bit mobile and desktop solution across the board. It's going to benefit their developers. It benefits Apple developers and those who develop for both iOS and OS X. Ultimately that benefits the customer as well.

      It's a given they will update the 9.7" iPad to the A7 (probably A7X), probably next month or by November.

      As far as 32-bit memory versus 64-bit, there are lots of "holes" in 32-bit address space. Moving to 64-bit eliminates that problem. Yes, there's a 2GB per process limit with 32-bit, and the iOS devices currently don't have more than 1GB let alone 2, but it's forward thinking...

      ...this move also allows continuous memory access, whereby the processor does not have to fetch from pages which aren't contiguous (next to each other), which will speed up applications that require this memory. Games, Photo and Video editing, etc. benefit from this.
      • It makes sense

        64bits makes sense but absolutely useless on 4" mobile. You ever wonder why cars got no 8 wheels than 4?
        • Re: You ever wonder why cars got no 8 wheels than 4?

          I for one, do not wonder. There are cars with 8 wheels. They have certainly some benefits over cars with 4 wheels.

          The screen size does not relate to the computing power of the device. An iPhone can output to 80" screen if you so desire.

          What is the point you try to make?
    • Ignorance is bliss

      It's amazing how many commenters on this and other sites are ignorantly writing the 64-bit iPhone 5S as a "gimmick".

      The benefits of the iPhone 5S 64-bit environment (64-bit A7 processor, running 64-bit apps, on 64-bit iOS 7) are HUGE!!!

      There is an article on All Things D today that explains what a radical improvement this is. Here are a few quotes from the article:

      “The fact that the A7 has twice as many processor registers means that more operations can occur without the processor using main memory, which is slower to access,” Carl Howe, VP of research and data sciences at the Yankee Group toldAllThingsD. “This means for that, for some codes, the A7 will be twice as fast (or faster, depending on how many memory accesses the original code had) to run code, because the processor doesn’t have to use main memory as much.”

      “The ARMv8 instruction set is clean-slate approach with many improvements. Even without 4GB of RAM, the A7 should make it easier to build larger applications like PC-class games and programs. Apps can now become real desktop-class programs and games.”

      "with the 64-bit A7, Apple has made it possible for developers to take the 64-bit apps they’re written for the Mac and bring them to iOS 7 with relative ease. And that is a huge benefit"

      “This will not be true with Android, by the way. The Android Java app and native app environment will need support from Oracle, who owns the Java environment as well as 64-bit support from the Android kernel. Android has a lot more moving pieces to coordinate, and will take longer to go to 64-bit.”
      Harvey Lubin
      • You guys didn't read my whole post

        You guys didn't read my whole post:

        64-bit is GOOD, and it's awesome that we're starting to stick it into phones now. I'm saying that there is no IMMEDIATE benefit (aside from some increased memory bandwidth that can only be utilized by core processes) to the iPhone 5S.

        Sheesh. Defensive much? Also, the iPhone 5S, if it really wanted to be a 64-bit power-house, should really have a minimum of 4GB of RAM to truly utilize the architecture.

        I'm HAPPY Apple stuck this chip in their phone because it will force others to do the same to compete, which means we'll get some 64-bit goodness. But for it to be of any use, we need more RAM, and apps that are designed from the ground-up to take advantage of it.
        • Alexia much???

          QMaverick: "I'm saying that there is no IMMEDIATE benefit (aside from some increased memory bandwidth that can only be utilized by core processes)" and "But for it to be of any use, we need more RAM"

          Read the quotes from the All Things D article I included in my original comment, or better yet read the entire article.

          "and apps that are designed from the ground-up to take advantage of it."

          ALL of the apps provided with the iPhone 5S are 64-bit... and that includes the large apps like iMovie, iPhoto, Pages, Numbers, Keynote, etc.

          AND there are going to be 64-bit apps from 3rd parties on launch day, including Infinity Blade 3. At the demo of Infinity Blade 3 on the iPhone 5S, the developer said it took only one person 2 hours to convert the 32-bit game to 64-bit using Apple's tools... so with conversion that easy, we should be many 64-bit iOS apps VERY quickly!
          Harvey Lubin
        • Re: there is no IMMEDIATE benefit

          How "immediate" is immediate for you?

          For example: you unbox your new iPhone 5S and *everything* is happening "immediately".
          Is this "immediate benefit"?

          RAM size does not make the difference between 32bit and 64bit. Processing does. With your freshly unpacked iPhone 5S, you "immediately" get a 64bit CPU, 64bit OS and 64bit apps.

          How more "immediate" it can get, I have no idea.
      • As for mentioning Android

        I mentioned Android because it was mentioned in this article.

        Also, 64-bit support is already popping up in the main-line kernel. As it's Linux-based, and the Linux kernel does support 64-bit architecture, I'm not sure where you're getting the idea that it'll be particularly hard to implement.


        The fact that ARM64 support has already shown up in the kernel means that they've been working on this for a while already. *shrug*

        Honestly, I don't really care--I'm excited about this announcement because it means the 64-bit arms race has officially begun, which is good for all of us, no matter which system you prefer.
        • Amen brother

          The point that QMaverick is trying to make to you seething apple fans is that pushing technology is GOOD. So in a few months when Android handset makers raise the bar, please applaud and congratulate instead of criticizing and saying specs don't matter. Basically, quit being hypocrites :)
      • Oracle does not produce Dalvik

        So no input from Oracle is needed (they don't make Eclipse either.)

        Furthermore, Dalvik code goes to an intermediate language (similar to Java bytecode) so moving that to 64 bit addressing is only just shy of trivial.
        • Love it

          I love it when people who know what they're talking about chime in. :-)
      • As huge as your head

        64bits won't help you a lot on small screen, will it as you can't really multitasking than switching between apps (32bit does that perfectly). If you got that for gaming than you are a sad case because xBox one and PS4 will do you better. 64bits is good for iPad but stupid for iiPhone
        • yes it is great for the Ipad, its the big winner

          Yet I am sure you would mock APPL for adding a 64-bit chip in the iPad and not on the iPhone. I can already imagine the uproar that APPL can't fit a 64-bit chip in their flagship phone.

          More people buy iphones than iPads, cause they can purchase the phone easier because of the subsidy. APPL just shifted the game back into their favor as GOOG, and samsung are going to have to actually get a 64-bit chip to work in their warez.