Guidance / Documentation on iOS 18.6.1 Blood Oxygen Saturation

The oxygen saturation data will be written to the Health store on the iPhone, but will NOT be synchronized to the paired Apple Watch. Apps can access the data using HealthKit APIs (.oxygenSaturation). If you see otherwise, please share here.

I'm unclear the measurement approach part. Hopefully folks who know the detail can jump in.

Best,
——
Ziqiao Chen
 Worldwide Developer Relations.

Hi Ziqiao,

Thank you for the response on this.

All your first paragraph points sound good. Unfortunately I too don't have an affected device so short of importing one, I'm not sure on the exact behaviour.

As for the measurements, yes any further details you can provide would be good including if the background measurements are still taken in the same way on these models and if data can be automatically synced back to iPhone and therefore the HealthKit database when the iPhone is available.

Thank you

Any updates on this? @DTS Engineer

Thanks

Going back to my original questions I think I have some answers forming:

1. Yes, SPO2 values are saved to Apple Health on iPhone
2. Yes, background measurements are now taken in the same way
3. Yes, the data is visible through the HealthKit APIs on iPhone only - not directly on Apple Watch
4. No, HealthKit does not sync these values back to the Apple Watch Health Store

Does this mean I'd have to use frameworks like WatchConnectivity to pass SPO2 data back to my Watch app?

Am I allowed to do that as seemingly Apple Health isn't?

Is there a better approach given the user's iPhone is most likely locked when using their Apple Watch and so the Health store on iPhone is unavailable?

Thanks @simonfromhelix for your following up and update. I'd like to confirm that, in the case you describe, the calculations and measurements are on iPhone, and the data is not synchronized to the watch.

Since the HealthKit store on the watch doesn't have the data, yes, you will need to manage to transfer the data with your own code, and Watch Connectivity is a choice.

Best,
——
Ziqiao Chen
 Worldwide Developer Relations.

@DTS Engineer this is helpful thank you.

Are you able to verify that doing this does not breach App Review or other terms as seemingly it's bypassing the same restrictions Apple has themselves had to implement?

Finally this does result in a poor user experience:

1. I don't know which user's Watches are affected, there's no API to query this? It's not actually region specific. Does the HealthKit source differ maybe such that I can observe that?
2. A separate syncing system is inefficient, less likely to be accurate and has all the limitations mentioned previously re. access to iPhone Health Store when device is locked

I presume there's not much to add on these points so I'll file a feedback but I do think this is confusing/misleading for users who otherwise presumably expect the SPO2 data to behave like any other.

Thanks for bringing up the potential policy problem. I indeed can't speak for the App Review team, and so would suggest that you contact App Review(login required).

I don't see an API that allows you to tell if an Apple Watch is impacted.

I agree that a separate syncing system is far from ideal, and yes, filing a feedback report is the way to go in this situation.

Best,
——
Ziqiao Chen
 Worldwide Developer Relations.