Fully support the increased HR & HRV data from Apple Watch Series 12 and Ultra 4
in progress
B
Benjamin Despont
With the new Apple Watch Series 12 and Ultra 4, Apple has significantly increased the frequency of both background heart rate and HRV measurements.
For heart rate, the watches now generate a background HR value approximately every 5 seconds. Apple’s 2026 Heart Rate Accuracy Study indicates that background HR data is published to HealthKit every 30 seconds.
Looking at my own Health data, I noticed that these measurements can be grouped into a single HKQuantitySample spanning several minutes. For example, Apple Health may show one ~5-minute sedentary sample with an averaged HR, while “Show All Quantities” reveals around 10 individual HR measurements inside it, each with its own timestamp roughly 30 seconds apart.
Would it be possible for Bevel to ensure it retrieves and uses these individual measurements — for example through HKQuantitySeriesSampleQuery / HKQuantitySeriesSampleQueryDescriptor where applicable — rather than potentially relying on the averaged value of the parent sample?
The same question applies to HRV. Series 12 and Ultra 4 also provide substantially more frequent HRV data. Since Bevel can calculate RMSSD from Apple Watch beat-to-beat measurements available through HealthKit, does Bevel already take full advantage of this increased HRV/beat-to-beat data?
If not, it would be great to expand support so Bevel can use the highest-resolution HR and HRV data that Apple makes available through HealthKit on these new watches.
And if watchOS or HealthKit provides any way for third-party apps to access even more of the new 5-second background HR stream, it would be very interesting to explore that as well.
One of the major improvements of the Series 12 and Ultra 4 is precisely this much higher cardiovascular sampling frequency. It would be great for Bevel to fully leverage that additional data for heart-rate trends, Stress, Recovery and other analyses, rather than effectively handling the new watches like previous generations.
Leah
updated the status to
in progress
Leah
Merged in a post:
Upgrade HRV to new ios27 data
Vince Pedicino
Can we get the updated ios27 metrics on HRV to be updated in bevel? Now that it's changed my data in bevel has degraded.
A
AE
Upvoting as an Ultra 3 owner upgrading regardless. Here's my honest calculus: I run my training around recovery and strain scores, and sparse overnight-only HRV is the limiting factor today. Apple is now publishing HR every 30 seconds and HRV every 5 minutes to HealthKit, and building its own Readiness score on top of it. If Apple's native scores incorporate the new data density and Bevel doesn't — if Bevel keeps reading averaged parent samples while Apple uses the full stream — I'll end up relying on Apple's scores instead. Full support for the new data is what keeps Bevel my source of truth.
B
Benjamin Despont
AE Il devrait pouvoir extraire les échantillons selon leur réponse. Bevel expands heart rate samples with count > 1 and processes the individual samples available through HealthKit. It does not rely only on the parent sample’s quantity. We also have an update coming soon that will improve support for Series 12/Ultra 4.