The man who uncovered Apple's software slowdown explains why you should still update your phone

  • Apple made a controversial decision to slow processing power to make sure older phones don't unexpectedly shut down.
  • John Poole, founder of software company Primate Labs, said Apple's approach to fixing the issue was reasonable, but the messaging was off.
  • Poole told CNBC that while Apple could have been more transparent with the changes to its software, it may not be the best idea to skip future updates.

Apple's latest software update may slow down certain phones — but that doesn't neccessarily mean you should skip installing the new iOS versions, one expert said.

Apple said Wednesday that it introduced a feature last year — tucked into software updates — for the iPhone 6, iPhone 6s and iPhone SE to "smooth out the instantaneous peaks only when needed to prevent the device from unexpectedly shutting down" when conditions were cold or as batteries aged.

The revelation confirmed research from John Poole, founder of software company Primate Labs. Poole's research found that iPhone 6s models running iOS version 10.2 and 11.2, and iPhone 7 phones running iOS 11.2, appeared to be more likely to have instances of lower processing speed.

Still, Poole told CNBC that while Apple could have been more transparent with the changes to its software, it may not be the best idea for iPhone owners to skip future updates.

"If you stuck with an older version of iOS, then what would happen would be your phone would be fast, but it might crash randomly," Poole said. "So that's really not an ideal situation if you're relying on your phone day to day, like most of us are. The other problem with holding back on security updates is you lose the security improvements and fixes that Apple makes with every release, thus putting you in danger of ... hackers and whatnot."

Poole's analysis led credence to a theory that had been making the rounds online, sending the conversation viral. A Reddit user testified earlier this month that the performance of their iPhone 6s had slowed significantly, but it returned to its prime speed when a new battery was installed. A flurry of commenters responded with similar anecdotes.

"We always hear some complaints about slow phones, and that's usually something that's gone on — maybe the phone's been damaged, or maybe there's a low power mode setting on, or something like that. But we saw a dramatic uptick in those sorts of reports around the release of iOS 11," Poole told CNBC's "Squawk Alley" on Thursday. "When I saw the Reddit post ... that sort of put two and two together for me."

Poole said Apple's approach to fixing the issue was reasonable, but the messaging was off. Apple could have avoided a lot of backlash, he said, by using phone messages or a toggle feature to alert users to the condition of their handsets.

"What I would have loved to have seen from Apple is for Apple to have come forward and said clearly and very bluntly what they were doing: That there was an issue with the battery. That the workaround was to slow the phone down, because the alternative would be to have the phone just suddenly crash," Poole said. "And basically tell the users ... 'If you want a fix, you have to replace the battery.'"