u/Fantastic-Badger-160

Long post, TLDR below.

I’ve been using iPhones since iOS 8, started building apps around iOS 11-12. Something’s been bothering me about iOS 26 and was also relating with people’s complaints on it. So I have a theory, which might be totally wrong.

I own an iPhone 14 Pro on iOS 26.4.2, the animations feel off under load, icon tinting looks random, Spotlight opening stutters, transitions feel loose. nothing crazy but it’s noticeable if you’re looking for it. Meanwhile my Geekbench records on this same device are higher than they’ve ever been on previous iOS versions.

That’s a weird contradiction i observed: Better scores, worse feel.

I was thinking back on iOS 12 on an SE 1st gen or iPhone 6. objectively which was way less powerful hardware but the UI felt almost deliberate, the transitions were consistent. it didn’t feel random.

I think Apple has been using a lot more compute on asynchronous programming by tuning their thread scheduler pretty aggressively over recent releases. For a non technical user’s perspective: more concurrent work happening = higher throughput = benchmark scores go up.

But more concurrency also means more contention. and on an A16 that doesn’t have a ton of thermal headroom, when multiple things spike at once you can starve the resources just long enough to drop frames. Which looks exactly like what i’m seeing.

iOS 12 like intentional consistency doesn’t seem to be the focus anymore.

Thus the benchmarks aren’t lying. there’s just more competing processes for that capacity than before.

TLDR Apple optimizing asynchronous programming like threading leading to benchmarks go up but also more contention under load leading to jitter, especially on chips with less thermal headroom like A16.

Would love to have your take on this.

Edit: Thank you stranger for the award 🙏

Hello everyone, I’ve been using iPhones since iOS 8 launched. And got interested into programming apps for Apple devices since then.

I own an iPhone 14 pro on iOS 26.4.2 and been lately observing that when I’m using it, the animations get jittery under heavy load. Tinting of apps in random order. While the geekbench scores being at an all time high for my device. These types of subtle observations got me some thinking behind it.

Apple seems to be using asynchronous & parallel programming a lot more for it’s on device processes in iOS 26.

Interesting fact is though on an older chip such as A16, I can observe the quality & transition of animations, scroll performance, swiftly opening spotlight search is not as smooth as latest iPhones.

This got me conclude that now more heavy operations are being performed on multiple threads eventually utilizing more CPU & GPU of my device. But these operations on previous iOS versions like 18 and 17 weren’t as much profound in compute. It wasn’t the case like this when I was using iOS 12 on iPhones such as SE 1st gen, 6, etc. The transitions felt structured in flow and less random.

Just a basic small observation I had using iOS all years.

TLDR: iOS 26 is utilizing asynchronous programming a lot more than previous iOS versions under the hood, leading to higher CPU/GPU usage on average while device physical capacity is the bottleneck. Thus Apple making utilization of said resources much more efficient leading to higher benchmark scores in iOS 26 but since the programming nature is non deterministic and more heavy resources are performed it explains people’s concern over quality of experience of the iOS.

Edit2: Sorry for my bad english. I was quite tired when writing this.