I never update an OS until at least the x.1 version and then wait at least 4 days

[TallManNY]

It’s hard to quantify that without numbers. I’m not saying that the battery life isn’t enough on every model after two or three major iOS updates, I’m saying that it’s worse than it was on its original version. Regarding battery replacements, I’ve found that they improve battery life when compared to a degraded battery on an updated device (which makes sense), but, if updated far enough, it can never match the original iOS version (even when the latter has a severely degraded battery!).

People generally don’t mind a moderate drop in screen-on time, especially on relatively current devices with good battery life and larger batteries, but that doesnt mean the battery life is good, just that the user finds it adequate.

I will give an example, the iPhone 6s: that device has, according to my experience and the experience of countless others, four tiers of battery life (I haven’t used every single iOS version, but I’ve used a few, and I’ve read about the others:

iOS 9/10: flawless battery life. It’s not perfect by today’s standards, but it‘s amazing when compared to later versions. It’s about 8-8.5 hours with light use, give it take a little based on usage, obviously. Go heavier and it’s lower, but for the sake of this comparison, let’s just pick light usage (web browsing, light reading, texting and other light apps on Wi-Fi only, low brightness).

iOS 11/12: Considerable drop, to about 5-6 hours of screen-on time. In terms of percentage, that matches the drop I had when Apple forced my 9.7-inch iPad Pro (with a similar processor, just better GPU) from iOS 9 to iOS 12.

iOS 13/14: Fell off a cliff. If it scraped 6 hours on iOS 12, it scrapes 4 on iOS 13 and 14. Here people started to really complain, many saying “I have to charge multiple times a day”. I tested an iPhone 6s on iOS 13 with 94% health, and it was about half of what I’m getting on an iPhone 6s on iOS 10 with 65% health. It probably stopped being fully useful as a full-day device with light use around here. (If not on iOS 11-12)

iOS 15: Even worse. it scrapes 3, it’s a shadow of its former self.

And there you have the tale of how Apple irreversibly ruined a perfect good iPhone in 7 years. Arguably, they ruined it in four. By 2019-2020 it was a shadow of its former self.

That is fascinating. The 6S is truly a good phone. Frustrating that Apple hasn't leaned into keeping these phones operational for longer periods of time. I suspect that there is concern about future sales of new phones. But I also suspect that service fees are proving more and more valuable and so growing the user base is seeming more and more important. The iPhone 14 being marginally more repairable is a good sign. Maybe in one of the future OS they will have a better battery saving feature which could be used to apply to older phones and save their battery life.

I'm still using a fully function XS. It has a replaced battery and it is kind of a secondary phone. So it never has battery life issues. But I wonder how it will run if I upgrade it to iOS 16. As you've noted, you can't really go back after you do that upgrade.

 

[FeliApple]

That is fascinating. The 6S is truly a good phone. Frustrating that Apple hasn't leaned into keeping these phones operational for longer periods of time. I suspect that there is concern about future sales of new phones. But I also suspect that service fees are proving more and more valuable and so growing the user base is seeming more and more important. The iPhone 14 being marginally more repairable is a good sign. Maybe in one of the future OS they will have a better battery saving feature which could be used to apply to older phones and save their battery life.

I'm still using a fully function XS. It has a replaced battery and it is kind of a secondary phone. So it never has battery life issues. But I wonder how it will run if I upgrade it to iOS 16. As you've noted, you can't really go back after you do that upgrade.

The 6s is my favourite iPhone ever. Like I said, I still use mine on iOS 10 and it is absolutely flawless. If it had more storage, I’d be able to use it as my main iPhone without any issues (app compatibility will start to be annoying, however). Camera would be bad, though, but I don’t take pictures at all, so it doesn’t bother me. Regarding the rest? Flawless.

It is operational, in Apple’s defense. Performance-wise, it is good, even on iOS 15. Perfect? No, but infinitely better than 32-bit devices. My point is, it is usable. Battery life makes it unusable as a main device, however, even with light use. Apple has come a long way with regards to improving performance in older devices, even if they aren’t perfect yet. I’m the first person to harshly criticize them due to them constantly obliterating battery life, but I have to give them credit where credit is due.

I cannot confirm your speculation. I don’t know whether the reason iOS updates keep destroying battery life is due to Apple not optimizing iOS hard enough, or if it is simply a matter of increased computation and what I require is not technically feasible. (I say require because I “fight back” the only way I can: by never updating. To update, I’d require them to be perfect battery life and performance-wise. They’ve come a long way, but they aren’t perfect, especially on battery life).

Apple has never been one of repairability, so I agree: I celebrate even a modest improvement in that regard.

Regarding what you said about future updates improving the battery life situation: I’ve lost hope. Apple touted the Xʀ’s battery life when it came out (it was its main selling point), and I was hopeful, only to see them obliterate battery life shortly afterwards. Apple touted the M1 as the next-generation, efficient processor on iPads. The impact of iOS updates there remains to be seen.

Your Xs will probably run fine performance-wise on iOS 16. Battery life is a different thing, though, and I wouldn’t be hopeful. (Extensive reports of battery life issues throughout every generation, even here: https://forums.macrumors.com/threads/ios-16-battery-drain-thread.2358921/).

The fact that, like you said, downgrading isn’t possible, precludes any attempt to say “I’ll just try it and go back”, unless you do that throughout the very short window in which it is possible.