Following the attention that Apple had gotten over the past few weeks regarding the discovery of mechanisms that reduce CPU frequency on devices with aged batteries, Apple has now issued a more comprehensive statement and apology addressing the matter:

First and foremost, we have never — and would never — do anything to intentionally shorten the life of any Apple product, or degrade the user experience to drive customer upgrades. Our goal has always been to create products that our customers love, and making iPhones last as long as possible is an important part of that.

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When power is pulled from a battery with a higher level of impedance, the battery’s voltage will drop to a greater degree. Electronic components require a minimum voltage to operate. This includes the device’s internal storage, power circuits, and the battery itself. The power management system determines the capability of the battery to supply this power, and manages the loads in order to maintain operations.

The statement doesn’t address any new information as to cause of the issue and confirms my initial technical explanation of the battery impedance causing the battery to no longer be able to supply a stable voltage supply during transient loads.

What we do have as new information is the various other effects that the throttling mechanism touches:

• Longer app launch times
• Lower frame rates while scrolling
• Backlight dimming (which can be overridden in Control Center)
• Lower speaker volume by up to -3dB
• Gradual frame rate reductions in some apps
• During the most extreme cases, the camera flash will be disabled as visible in the camera UI
• Apps refreshing in background may require reloading upon launch

Some of these points regarding frame rate reduction might also point out that iOS is also limiting the GPU frequency, among other unexpected limitations such as lower speaker volume and screen dimming.

Based on the large media attention and relatively negative feedback which prompted Apple to this second official response and statement, Apple promises three key points to address consumer’s concerns:

• Apple is reducing the price of an out-of-warranty iPhone battery replacement by $50 — from $79 to $29 — for anyone with an iPhone 6 or later whose battery needs to be replaced, starting in late January and available worldwide through December 2018. Details will be provided soon on apple.com.
• Early in 2018, we will issue an iOS software update with new features that give users more visibility into the health of their iPhone’s battery, so they can see for themselves if its condition is affecting performance.
• As always, our team is working on ways to make the user experience even better, including improving how we manage performance and avoid unexpected shutdowns as batteries age.

Reduction of the cost of an official battery replacement from $79 to $29 is a much welcomed change that makes this a much more attractive option considering replacement batteries only cost $10-15 depending on model; Apple’s previous pricing at $79 was extremely extortionary given the critical aspect of this service. I would now recommend any users who hesitated on replacing their iPhone batteries on their own to make use of the official service as it will have very noticeable impact both on device battery life as well as device performance (due to the nature of this story).

The way that Apple has handled disclosure on the throttling mechanisms has also been heavily criticised as users felt their devices slowing down with iOS updates and not knowing the reason. Here Cupertino promises key changes in the way that iOS handles information sharing on battery health and reporting, as well as promised improvement on performance management under degraded battery conditions. The issued time-frame for when we can expect these updates are “early 2018”.

Overall the response from Apple was the only possibly correct one to the whole fiasco, and the only one which was to be realistically expected, though it took longer than it should have to implement changes such as drastically reducing the battery replacement cost.

Source: AnandTech – Apples Issues Updated Statement On Battery Ageing