:wave: Hi everyone! At our company, we are facing...

# compose-ios

[Tadeáš Sosín]

👋 Hi everyone!
At our company, we are facing a severe performance issue regarding frame pacing on newer iPhones (e.g., iPhone 15 Pro, iOS 26.3).

The Problem: Whenever the iOS system performs high-priority UI updates outside of our app, Compose Multiplatform apps start heavily stuttering during scrolling and animations. While this is most easily and consistently reproduced when Spotify (or any app using Dynamic Island) is running in the background, it is not limited to the Dynamic Island. We occasionally observe the exact same massive frame drops during app transitions, or simply when a standard iOS push notification drops down while the user is interacting with the app.

What I tried (Nothing helped):
• Updating to the latest Compose/Kotlin versions.
• Enabling parallelRendering = true.
I created YouTrack where you can find more -> https://youtrack.jetbrains.com/issue/CMP-9821/iOS-Severe-frame-drops-and-stuttering-when-system-overlays-Dynamic-Island-are-active

Are we missing something obvious? Has anyone else encountered this? It’s not just our apps where I can see the problem 😢 I’m looking for a workaround 🙈

Thanks for any pointers! 🙏

[Jonathan]

Does this issue happen on iPhones without a dynamic island but running iOS 26.3

[Jan Kusý]

yes

[Jiri Bruchanov]

i'm facing similar issue...
on iphone 15... last 3 major ios versions...
upgrading to compose 1.9 or newer made it slightly better, but the problem still exists

[Jiri Bruchanov]

iphone 17 pro max is fine, but it might be just because its faster ?
i've added simple fps counter and looks like ip15 drops to 30ish for few seconds and then goes back to 60...

usually for me reproducible just by switching apps

[Andrei Salavei]

Hey! I'll take a look there. Can someone try the latest 1.11.0-alpha03 with parallel rendering enabled ?

[Tadeáš Sosín]

👋 I'll try it, thanks!

[Jiri Bruchanov]

I'll try it later today, thanks 👍

[Tadeáš Sosín]

@Andrei Salavei I have to run away, but I just quick tested following -> KMP App Template, branch agp9, compose 1.11.0 alpha 3, parallel rendering

I don’t have time to test properly, but first impression is good, because I cannot reproduce the problem 😍 later I’ll give you better report.

[Jiri Bruchanov]

after 5mins of trying, can't reproduce it... 🎉

[Michal Janecek]

@Jiri Bruchanov did you happen to test while Dynamic Island was actively updating (e.g., Spotify playing / Live Activity changing)?
I updated from 1.11.0-alpha02 → 1.11.0-alpha03 and it completely fixed the scrolling/FPS drops on my iPhone 14. But on a newer iPhone with Dynamic Island active, I still see a severe performance hit (maybe slightly improved vs before). Curious if you can reproduce specifically under that condition. Thanks!

[Jiri Bruchanov]

@Michal Janecek
I was just testing my case, no Dynamic Island involved

[Jiri Bruchanov]

is there anything extra what needs to be done other than starting spotify ?
It seems to be working fine

[Jiri Bruchanov]

the only difference I can see is that when is spotify playing...
I see my FPS counter dropping to approx 20FPS for <1s when I turn on the display again...
then goes back to 60s, which doesn't seem to be happening (or its way shorter, not noticable) if spotify doesn't play

[Michal Janecek]

Thanks for the report, just starting Spotify should be enough if you see it playing in the dynamic island. In our case it is a difference between almost perfect experience (no spotify) and annoying scroll lags (with)

[Jiri Bruchanov]

Any difference if you rotate the app to landscape?
(the island seems to be inactive in landscape)