A Reddit post from an iPhone 6s owner reported that a battery replacement significantly increased the device's performance running iOS 11. The ensuing discussion thread, also picked up by readers in the MacRumors forum, seems to indicate that Apple intentionally slows down older phones to retain a full day's charge if the battery has degraded.
According to TeckFire, the author of the original Reddit post, its iPhone had been slow after updating to iOS 11, especially compared to his or her brother's iPhone 6 Plus, so decided to do some research with GeekBench and battery life apps, and ended up replacing the battery.
“Wear level was somewhere around 20 percent on my old battery. I did a Geekbench score, and found I was getting 1466 Single and 2512 Multi. This did not change whether I had low power mode on or off. After changing my battery, I did another test to check if it was just a placebo. Nope. 2526 Single and 4456 Multi. From what I can tell, Apple slows down phones when their battery gets too low, so you can still have a full days charge.”
Apple launched a repair program for iPhone 6s owners after some users reported their devices were unexpectedly shutting down. Apple said the problem was down to a manufacturing issue affecting a "very small" number of iPhone 6s devices, and offered battery replacements free of charge to owners of devices within a limited serial number range.
Then Jobs' Mob released iOS 10.2.1 and said the update resulted in an 80 percent reduction in unexpected shutdowns on iPhone 6s and a 70 percent reduction on iPhone 6 devices.
Apple claimed that this was because it was fixing a more widely reported bug caused by uneven power delivery from older batteries, and claimed it was separate from the manufacturing fault that had caused it to recall a select number of iPhone 6s devices.
However, Apple fanboys on this Reddit thread, speculates that the two shutdown issues are related. In other words, Apple's fix involves dynamically throttling the phones' maximum clock speeds relative to battery output (voltage), to prevent them from drawing too much power and shutting down.
This is not the first report that replacing the iPhone 6 battery can improve the performance. But the idea of Apple is intentionally throttling the performance of older devices is heresy. After all the only thing Apple has to gain from such action is to force users to upgrade to its latest range of more expensive phones and that is not a motive.
Not all Apple fanboys are hacked off. Some of the comments dub the claims “fake news” and the Geekbench scores as “fake science”.