Apple's move to 64-bit with its A7 system-on-a-chip (SoC) inside the iPhone 5S gives the Cupertino, Calif. company the flexibility to launch a new line of tablet-based devices to replace at least some Intel-driven Mac personal computers, analysts said today.
"Where the A7 starts to make a difference is in the iPad, where much more memory intensive applications are possible," said Ben Bajarin, an analyst at Creative Strategies. "There could come a time when the only Mac running x86 [processors from Intel] is the Mac Pro, and ARM bleeds up to the lower-cost Macs."
Last week, Apple revealed that the A7 SoC powering the new iPhone 5S relies on a 64-bit, custom-designed processor licensed from ARM, the U.K. chip design company whose silicon sits inside virtually every smartphone and most tablets.
While some analysts struggled to see the advantage of 64-bit inside a smartphone -- the technology's most obvious benefits come only when it addresses more than the 4GB memory limitation of 32-bit CPUs, an amount not yet seen in phones or tablets -- Bajarin and others said there was plenty to tout short-term.
"A lot of people have glossed over the A7," said Patrick Moorhead, principal analyst at Moor Insights & Strategy. "There are advantages for the iPhone from the ARM V8 instruction set, an improved instructions-per-clock and improved cache, subsystems and a new GPU [graphics processor unit]. You won't see a performance increase in applications that require less than 4GB of memory, but that doesn't mean the A7 isn't important."
Moorhead, who was once the marketing manager at AMD when that processor maker transitioned to 64-bit, said the 2X performance increase trumpeted by Apple last week came from the A7's multiple improvements over the 32-bit A6 that ran last year's iPhone 5 (and this year's iPhone 5C).
"I think a lot of people missed why this matters now," added Bajarin in an interview. "Apple did a lot of very good optimizations [with the A7] for performance benefits with iOS 7 right now. The iPhone is tangibly better now, so there is a short-term impact."
But both analysts saw the A7's future possibilities, driven by its 64-bit architecture, as much more important than the immediate payoff in the iPhone.
The 64-bit processor, which Apple went out of its way last week to describe as "desktop-class," will likely power the refreshed iPads most expect the company to reveal next month. That opens up all kinds of opportunities for Apple.
"You can be productive on a 10-in. screen," Bajarin argued, citing the iPad's display size. "But you need more computing power for productivity tasks." And the 64-bit A7, along with more system memory, would provide the necessary power to run desktop-class applications like those now segregated to OS X and the Mac line of personal computers.
Bajarin envisioned iOS devices very similar to today's iPad that could handle the bulk of the chores now the provenance of Windows and OS X desktops and notebooks. "For business workers, [such a] tablet could be the only computer they have. When they want a bigger screen, they just dock it with a big screen," said Bajarin. "The tablet would be the desktop."
From his perspective, Apple's use of the A7 in the newest iPhone hints at ambition beyond the smartphone -- tablets and tablet-style Macs -- with that ambition likely to show results much sooner than most expect.
Moorhead agreed. "This allows Apple the flexibility to move iOS upstream to clamshells and convertibles and even desktops if they wanted to," Moorhead said. The 64-bit A7 positions iOS as a platform for the core requirements of desktop computing, which now takes place on Intel processors, including content editing, multi-tasking, gaming and something Moorhead called "content density," or the size of the files being manipulated.
"It gives Apple the ability to take iOS wherever they want," contended Moorhead. "It could be a transition step to a lot more powerful devices, ones that have more ability to edit content not just consume it."
That transition could be a convertible device priced between the current iPad's $499 and the $999 entry-level 11-in. MacBook Air notebook, Bajarin said. The ARM architecture would boost battery life even further than the "Haswell" Core i5 now in the Air -- assuming the same-sized case and thus battery size -- but retain the portability of a tablet since a keyboard would not necessarily be part of the package.
Microsoft has tried, with little success so far, to market its Surface tablets -- especially the Intel-inside Surface Pro -- as a dual device. In addition to being a tablet, with its cover keyboards or when docked at a desk, it can also be used as a notebook.
Bajarin acknowledged the similarities between his thinking on an expanded Mac line and Microsoft's Surface concept. The advantage Apple has is a well-stocked app ecosystem and millions of developers eager to write for iOS, as well as its working from a position of strength in the tablet market. Microsoft has to claw for every digit in share because it was late to the tablet party.
A swing to 64-bit and the ability of iOS to run much more ambitious software could also portend a blending of iOS and OS X, Apple's two operating systems, on new devices. Or Apple could reuse a tactic from the days when it switched from PowerPC to Intel processors in its Macs to allow those devices to run software from both camps.
"Apple's transitional tools have always been pretty good," Bajarin noted, mentioning Rosetta, the binary translation tool that let Intel Mac owners run most software written for the PowerPC. "If you have the CPU power, [running a translator or emulator] is a moot point," he added, again citing the A7 and its 64-bit architecture.
Neither Bajarin or Moorhead imagined a timetable if Apple decides to use the A7 and 64-bit as a jumping-off point for new devices, a smart move because of Apple's ability to keep new projects -- if not new iPhones -- under wraps.
But Bajarin had signals to look for. "It'll be interesting to watch what developers do in the next three, four months [on A7-equipped iPhones and iPads] that they couldn't do before, that were earlier available only on the desktop," he said.
Moorhead cited other signs he would track, most importantly the progess Intel makes in pushing forward on its efforts to create powerful processors that require much less battery power, like Haswell.
"Intel has done nothing but accelerate," said Moorhead of those moves. "It's not letting up."
If Apple wants to differentiate its hardware from the greater volume of devices produced by Windows OEMs (original equipment manufacturers), it will want to separate itself from Intel, the supplier of most of the world's CPUs.
"Apple could take [the ARM] design up the stack as far as they possibly can," said Moorhead. "There's no reason why they couldn't push this further and further. It would give them a pretty big advantage, with one tightly-integrated team that actually builds the software and the hardware at the same time."
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His email address is email@example.com.