Why the 64-bit chip in the iPhone 5s matters

Apple’s iPhone 5S is the first device to ship with an Apple A7 chip. And that happens to be one of the first 64-bit processors based on the ARMv8 architecture. While one of the key benefits of moving to 64-bit memory is support for up to 16 exabytes of memory, it’ll probably be a few years before Apple actually ships an iPhone or iPad with more than 4GB.

In fact, the iPhone 5S has just 1GB of memory (at a time when many high-end Android phones have 2GB or even 3GB).

So why is Apple the first company to release a phone with a 64-bit chip?

iphone 5s

There could be a few reasons.

  • Apple will eventually release devices that need more memory — and by starting now, developers have a few years to get their apps ready to support 64-bit architecture. Since the A7 chip can also support 32-bit apps, it’s compatible with most older iPhone apps. But it’s also the first in a new series of chips that pave the way for the future. When the future arrives, the iOS ecosystem will likely be ready.
  • ARMv8 architecture doesn’t just increase the memory capacity — it also features a new instruction set which boost performance and reduces power consumption.
  • Certain apps (including games) will be able to make use of that new instruction set, and acess to additional registers in the A7 chip to boost performance.

In fact, AnandTech ran a series of benchmarks and found modest-to-huge performance gains when running certain types of tasks using the new iPhone’s 64-bit processor. Built-in support for AES encryption offered performance gains of more than 800 percent in cryptographic tests. Other gains were much more modest, but 64-bit performance seems noteworthy in almost every test.

All told, Apple’s A7 chip is probably the fastest ARM-based processor on the market today. That may not be true once competitors start to release their own ARMv8 chips in 2014, but it’s clear that Apple isn’t just looking toward a future where iOS devices use more than 4GB of RAM. The A7 chip is for today as much as for the future.

And when Apple does complete the transition to 64-bit in a few years, the iPhone 5S will b the oldest iOS device that still works. So the move isn’t just about Apple preparing for the future… it’s about users buying a piece of hardware that’s a bit more future-proof than the iPhone 5C.

To sum up: Apple’s new A7 chip is faster than any iOS device to date, even if there isn’t much iOS software that takes full advantage of 64-bit processing yet. That’s because it’s based on the ARMv8 architecture which is faster and more efficient. At the same time, this phone will have a longer effective lifespan than any other iOS device released to date since it’ll be able to support 64-bit software if and when there’s a day when that becomes a minimum requirement for iOS.

  • jm2c

    Unless something else comes up 64bit is the logical path for mobile chips. At some point they will have to all support 64bit chips. It’s better to do it sooner than later. Windows took a long time to go fully 64bit because of all the applications and drivers that didn’t play well with it.

  • Anon

    There are a few reasons why the 64 bit is important. Laying the groundwork for the future.

    Remember how the original XBOX & Playstation came w/ 256 & 512MB of RAM. There are companies now releasing iOS7 game controllers.

    Imagine a new 4K compatible AppleTV complete with a solid library games at launch. They’ll need a machine with at least 8GB of RAM to compete against the current, new XBOX/Playstation.

    Next, it is easier to migrates OSX apps to iOS since both now have a closer code-base. This makes it easier for OSX apps developer to port their software to iOS. This is the biggest gain.

    I can see all the pretty awesome graphis and music apps easily ported to iOS now.

    The whole meme that you need 4GB to realize the advantage of 64bit is hogwash. I was running 64 bit workstations from Silicon Graphics and Sun Microsystems in 1994. Those machines had 2GB of max ram yet they all ran 64bit architecture.

    The PowerPC G5 was 64 bit and most systems were 1-2GB of RAM. There is a real advantage when all the apps and libraries go 64 bit.

    This is a bigger uphill battle for Google. Sure, Linux is 64 bit. Dalvik may need some work. the GCC compiler was recently updated just this summer to support 64bitARM.

    It will be about a good year before any momentum in Android takes place.

    However, the biggest drawback will be device drivers. Unless all the manufactures of all the sub-components deliver 64 bit drivers, running Android w/ a SOC and OS will be handicap by that.

    This is what plague the desktop 64 bit transition. Apple does everything vertically and have a tighter control on their hardware.

    Strategy wise, Apple is doing it now to ease the pain for the future. They are masters at architecture transistions: Motorola 68k ->PowerPC ->Intel/X86.

    They know what they are doing with FAT/universal binaries. They also have the advantage of speeding up developers to go only 64 bit in 2 years. They have no problem of dropping architecture (32bit ARM) when they have the developers in tow.

    Just look at the number of iOS 7 optimized apps already out to make this point. It is basically just a check-box tick to recompile for Universal 32/64 bit.

    Google doesn’t have that luxury nor track record. There will be low-end and high end devices. in 2-3 years, I can see iOS ecosystem as 100% 64 bit only with no legacy cruft.

    Whereas there will be different manufactures in Android providing a mix of 32/64 bit. A majority of those developers run Dalvik DEX anyways so they have no incentive to go native compiled C bare-metal 64bit where you see the advantages.

    This is a win for Apple. Not to mention the next iPad will be a monster.

    • Renaldo V

      Why will the next iPad be a monster I don’t get it. I’m planning on buying the next iPad but all this talk about a7 isn’t worth it is confusing me.

  • inkflow

    Other than preparing for the future 64bit in the iPhone 5s which is good for future iPhone models. Current owners of the iPhone 5s benefit nothing from the transition to 64bit. The better encryption you mention has nothing to do with the chip having 64bit address space.

    BTW, keeping the RAM of the 5s only at 1GB limits the future of the 5s much more than the future looking 64bit processor. 5s owners are not going to enjoy memory hungry future 64bit applications.

    • Daniel Lundh

      Maybe you should have read the Anand piece before putting your foot in your mouth.

      • inkflow

        I read Anand’s article and I stand behind what I said.

        Apple added encryption acceleration to the CPU so it is no surprise that using this acceleration is indeed faster. This has nothing to do with 32 and 64 bit CPUs.

        Also, running 32 bit code on a 64 bit CPU probably needs some emulation layer – so you can’t expect a 64 bit CPU to run 32 processes as fast as a native 32 bit CPU.

        Moreover, 64 bit processes consume more memory than 32 bit processes – like it or not an 8 Byte pointer is twice as long as a 4 Byte long pointer. In modern languages pointers are in abundance so a 1GB is less useful on a 64 bit platform than it is on a 32 bit platform.

        64 bit CPUs are indeed the future of mobile computing. But with less than 4 GB of RAM you will never enjoy the real benefit of a 64 bit processor – and this is my friend is the increased memory space.

      • Daniel Lundh

        This is a lose/lose scenario. If Apple had stayed 32-bit they would have had their ass handed to them. When they went 64-bit they got their ass handed to them.

        They can’t do anything right I guess.

      • mehrab

        I tested infinity blade 2 (32 bit app) and infinity blade 3 (64bitapp) on the 5s. So the 32 bit app was on memromy (ram) while i did heavy multitasking for about 3 minutes. The 64 bit app was there for 4:56 seconds while i did the same heavy mutitasking as i did before but opened 2 more apps. You seem like your very techy but you seem like you dont own a 5/5s and that you use android use a someones 5s/ 5 compare it with your 2-3 gb rammed android phone such as gs4″s, htc ones lg g2″s nexus 4″s note 3″s or whatever you”ll be shovked when ypu see the 5s actually beats most of them/keeps up with them in real world usage in terms of ram efficiency , app lauching etc go to youtube if you cant. How does the 5s do this? IOS OPTIMIZATION And 1gb of 5s is gddr3

      • Gregory

        Lool, you can’t compared a older generation game with a newer. Every years, hundred of apps are optimizied to run more effective on operating systems. Things like less RAM, OpenGL ES support, etc. Sure iOS is far more effective than Android or any other operating system, but that’s because Apple only focuses on a few device models, not like Android that has to be developed and optimized for nearly 500+ devices yearly. Even then, Android is becoming dominate as we speak. No longer is it laggy in anyways with new device models. Even old models like the Samsung Galaxy S2 can run stock Android in a breeze. I think apple has come to the point that their motto “it just works” is coming to an end. Sure it works, but so does every other device on any other operating system. If they wanna become superior they are going to have to open the close down ecosystem of theirs.

  • Zach Ellis

    Lol. Everyone who owns an iPhone won’t want a 3 year old 64-bit phone, they will want a brand new 64-bit phone.