I left an Apple iPhone 6s in a hot car once. I didn't think too much about it at the time, and the phone seemed to work normally for a few months after that. I remember seeing a message on the phone about powering down because of an overheating issue.

Then, just recently, I upgraded it to iOS 11. At the time, I couldn't really account for the strange sense that the phone seemed slower, and I couldn't confirm it. I even wrote about the problem, having read a report that said it was all in our heads. I chalked it up to perception and the sense that newer phones are, of course, much faster. 

It turns out, I was only half right. Apple has now admitted to throttling older iPhones that use the latest operating system. It's a way to deal with a battery issue like the one on that iPhone 6s I used a few months ago. In fact, Apple has been doing this "fix" since before iOS 11 ever came out. As the battery ages, the "peak performance" routines (say, heavy gaming or--ironically--running a benchmark) on the phone tend to cause problems and make the phone turn off suddenly, so Apple released a fix for that earlier this year. As they say in computing, it's a feature not a bug. Except that there is one pretty serious complaint here, and fortunately one very obvious fix that will solve the problem.

First, about that complaint. There's a long history of Apple being secretive about new product announcements, and also about explaining some of the back-end issues (you could argue this protects the company's interests). When Apple announced the fix for the battery issues, the company didn't exactly spell out how the phones would be slowed down automatically as part of the solution, and it didn't give users a way to adjust those settings or even disable the option (and live with the unexpected shutdowns).

Apple released a statement to Inc.com and others to explain the slowdown:

"Our goal is to deliver the best experience for customers, which includes overall performance and prolonging the life of their devices. Lithium-ion batteries become less capable of supplying peak current demands when they are in cold conditions, have a low battery charge, or as they age over time, which can result in the device unexpectedly shutting down to protect its electronic components. Last year, we released a feature for iPhone 6, iPhone 6s, and iPhone SE to smooth out the instantaneous peaks only when needed to prevent the device from unexpectedly shutting down during these conditions. We've now extended that feature to iPhone 7 with iOS 11.2, and plan to add support for other products in the future."

That seems like a fair description, if a little late to the party. At the same time, is it actually a conspiracy? Not at all. Apple is not forcing people to upgrade to the latest phone after they upgrade to a new OS. I'm not sure about the legal issues there, but it would be extremely counterproductive. As we all know, if it was all a ploy, someone would figure it out eventually. Instead, Apple was quietly fixing a bug (it claims).

I have another concern. That original benchmark claimed phones did not slow down at all, and I believed it. Futuremark conducted the tests, and a representative told me the bench-marking is still valid. The tests were based on 100,000 benchmark results.

"We stand by our original analysis that iPhone CPU performance in older models does not change with iOS updates, provided that the battery can deliver the required power," the Futuremark representative stated. "The CPU in an old iPhone with the latest iOS and a good battery can perform to the same level today as it did when new. This is backed up by the users who report that the performance of their device returned to the expected level after replacing the battery."

It seems odd, though. So does an older iPhone actually run slower? If your battery is fine, it should run at about the same speed. If you have a defective battery, it will run slower.

Fortunately, there is a fix. If you do have an older iPhone that seems slow after upgrading, you can pay $79 for a replacement battery. It's likely the phone will recognize the new battery and keep running at the fastest speeds possible, without any throttling.

The story is far from over, though. There is no conspiracy. What everyone is missing is that Apple still needs to explain how this happened, and that's not something the company has done in the past. This may be an opportunity to correct that perception.