Battery life for my watch face seems a lot worse since WFS 1.4.20

I rebuilt my watch face on WFS 1.4.20 and now the battery life for it seems a lot worse. I do have HR displayed using the [HR] tag. I noticed they changed how it behaves… It seems to now sync with the watch HR settings (Like the Samsung Health setting on Galaxy Watches) instead of using tap to update/measure before. So if my option is set to measure every 10 mins, it will update every 10 mins. Well Pixel watches don’t have the option to change that, so it should continuously update. I have noticed a significant decrease in battery life on my Galaxy Watch and Pixel Watches (according to customers) and this might be related to it, has anybody else had issues? It seems strange because it’s not like it’s using the HR sensor on the watch any more than it used to, just pulling data from it similar to how Samsung Health would. It may not even be related to HR, but that’s one of the most notable changes to the watch face since it was built on WFS 1.3.13. Has anybody experienced any issue like this?

Watch face:

The only time I have an issue with the GW5 watch battery life is when I forget to turn off the Debugging.

See FAQ 12 about Heart Rate

The release notes for the WFS 1.4.19 mention the removal of measuring HR.

No watches continually update the heart rate as far as I know they only do it when activity is detected.

Maybe someone else is noticing something

Samsung Developer Relations

Sorry to revive a stale thread, but this is definitely incorrect. My Pixel Watch continuously updates the displayed Heart Rate in a Complication no matter what. When the watch is awake, it repeatedly blinks changes in heart rate about every second. I don’t think it’s possible to stop it from doing so, actually. Perhaps if you don’t pair it with Fitbit it doesn’t continuously monitor it, but it is definitely monitoring my heart rate with a high refresh rate. That continuous refreshing is something Fitbit users have expected for years, which I believe is why Google doesn’t even let you turn it off, despite the severe battery trade-off on a watch largely agreed to have poor battery life. I’m surprised to hear that Samsung possibly isn’t keeping step with that user expectation.


I stand corrected, this is possible in Wear Health Services API It is called seriesData and with Samsung Health it is only displayed during activity.

SeriesData: a RawData object that encapsulates a sequence of measurements over a period of time. SeriesData is particularly suited for high-frequency sensor data, such as continuous heart rate samples during an activity session

Wear OS requires for two Heart Rate measurements it has both but when to display them is up to the watch face app.


Anyway with Wear 4 and and WFS 1.4.x the heartrate measurement will be whatever the user sets on the watch.

Samsung Developer Relations


Thank you for the detailed clarification!! Wonderful!