Last week, 9to5 Mac reported that iPhone 6 and 6s slowdown and shutdown issues could be solved by getting a new battery. When a group of iPhone 6s users reported their devices were shutting down randomly, Apple launched a repair program offering free battery replacements.
Later, when seeing that a larger number of iPhone 6s users were having the same issue, Apple released an update in iOS10.2.1 that dynamically changed the maximum clock speed relative to the voltage the battery was outputting, so the phone couldn’t draw excessive power and shut down. Apple stated that the shutdowns were reduced by 80% for iPhone 6s devices and by 70% for iPhone 6 devices.
A Reddit thread this past weekend offered evidence about how the update actually changed phone performance. Many users found that the software update did not improve the shutdown issue, and in fact slowed down their devices. In contrast, a common finding from the Reddit thread was that replacing the battery improved performance, in both real-world and benchmark testing. 9to5Mac founder John Poole also conducted in-depth testing to explore the relationship between iPhone performance and battery age. He plotted the kernel density of Geekbench 4 single-cores scores for the iPhone 6s and iPhone 7 running different versions of iOS. See the results.
Poole found that performance issues increased steadily for the iPhone 6s moving from iOS 10.2.0 to 10.2.1 to 11.2.0. The iPhone 7’s performance did not have any issues until the test with iOS 11.2. Poole stated, “First, it appears the problem is widespread, and will only get worse as phones (and their batteries) continue to age. See, for example, the difference between the distribution of iPhone 6s scores between 10.2.1 and 11.2.0. Second, the problem is due, in part, to a change in iOS. The difference between 10.2.0 and 10.2.1 is too abrupt to be just a function of battery condition. I believe (as do others) that Apple introduced a change to limit performance when battery condition decreases past a certain point.”
Poole believes that Apple added a software adjustment for the iPhone 7 with iOS 11.2, similar to what it did to correct iPhone 6s shutdown issues with iOS 10.2.1. According to Poole, Apple may have unscrupulously created a “third state” with slower iPhone performance without notifying customers, in order to motivate them to upgrade their devices sooner than planned. According to Poole, “While this state is created to mask a deficiency in battery power, users may believe that the slowdown is due to CPU performance, instead of battery performance, which is triggering an Apple introduced CPU slow-down. This fix will also cause users to think, “my phone is slow so I should replace it” not, “my phone is slow so I should replace its battery.”
Much like Poole’s findings show, some Reddit users speculated that since Apple had an overflow of battery replacement requests and did not want to replace all of them, the company instead throttled iPhone 6s devices with a software update to “solve” the shutdown issue.
It should be noted that Apple says that iPhone batteries are only designed to last for about 2 years’ worth of charge cycles. This, along with the seemingly intentional masking of fixable battery issues for older phone models, point to the goal of planned obsolescence.