Hello guys, I have tested this intensively yesterday and I think the behavior has changed after the recent TW3 Pro firmware update… I trying different sequences of sensor initialization and I’m able to get SPO2 data for a short moment, but over night tests usually end with no SPO2 tracked… I will keep trying…
I do not know yet. I did not manage to test all the combinations. So any feedback appreciated…
I’m going to get a TWP3 in a few days, so I’ll be able to help troubleshooting the issue. Does Mobvoi provide no info on how to initialize and access sensor data? If they are not doing it the standard way (which is a very bad thing), they should at least document it somehow.
Hello, yesterday I tied to disable HR altogether in Settings > Wearables and only leave the Oximeter setting on and I did get all SPO2 data on that night… this needs more testing, but to me it seems like after the firmware update the sensor is even more sensitive on the use of any HR sensor and does not work in this case… So I’m affraid it will be either HR and HRV or SPO2 on the TicWatch 3 Pro…
Hello, anyone any observations? Today I’m trying to re-register the sensor listener every time an error is returned from the sensor… so hopefully this will help…
Google at I/O has announced major changes to how apps can access sensor data in the next version of Wear OS (wow! big changes finally!) here, in the Devs insights video. Maybe this can help?
[kind of OT side note]: since in the same video they have announced a collaboration with Sleep Cycle for Wear OS, would you consider a standalone Wear OS app? I think it would be a great addidion, given the great revamp and changes given to the platform.
1 Like
Also, in regards to this particular way: if it works, then it’s great - but wouldn’t constantly re-registering the sensor drain more battery?
@mind-overflow was watching the video in the morning. Definitely great news for the platform which is now after Pebble is gone my favorite. Unfortunately I did not yet find any documentation for the new Health Services API so hard to say if this would really be something of a use for Sleep as Android…
Regrading battery when reregistering sensor… my theory is that after the update, when the SPO2 sensor misreads data - for instance you are laying on the hand or similar… it just reports error and stops sending data. I expects this happens only few times during the night so expected battery impact is negligible IMHO…
1 Like
That sounds like an absolutely plausible explanation to why the sensor stops sending data. I was expecting it to be more of a random thing that happens every few minutes.
If this is the case, then, i think the “fix” of re-registering it would be great, given that the app doesn’t insist on that if the sensor keeps reporting errors (eg: retry only 5 times in a row, then give up for the rest of the tracking, or even for X minutes). It would be sad to wake up in the morning with a discharged watch because the CPU was busy all night trying to access the sensor.
By the way, I don’t know what kind of certainty you have on this theory, but if you want to be more sure, a simple test of manually starting tracking and removing the watch should make it evident (given that you obviously can see logs and print stuff to the logs too).
Is this fix already implemented in the latest version? If so, I could help testing or giving feedback if you need it in any way!
Thank you for your commitment 
Hi guys,
Nothing really to add to the discussion - just wanted to jump on and let you all know I’m happy to test fixes for this issue.
Cheers,
Nick
Many thanks. I will prepare some version for testing hopefully next week…
Hi, just chiming in to say I have the same observations. Discussion and thoughts for solution seems like good ideas. Looking forward to results 
Hi all, I was testing this over the last week and for me if I disable HR tracking and just enable the Oximeter option I’m getting SPO2 data the whole night in 100% cases when I start the tracking both from the watch or from the phone. I;m still having some issues with automatic sleep tracking which I will be look at this week…
I anyway would like to test this out you need the latest version of Sleep as Android from the BETA channel and also the latest Wear app from the BETA…
They are available here:
https://sleep.urbandroid.org/wp-content/uploads/release/wear-beta-release-4.4.apk
https://sleep.urbandroid.org/wp-content/uploads/release/sleep-20210524-beta-release.apk
Or you can opt-into the BETA channel like this:
Please first join our BETA Testers group at:
https://groups.google.com/forum/#!forum/sleep-as-an-droid
That you can opt-into the BETA at the following address:
https://play.google.com/apps/testing/com.urbandroid.sleep
or simply by visiting our Play Store listing and tapping “Join BETA”
The latest Wear app has a new feature, if you start the app during sleep tracking you can control sleep tracking from there PAUSE/STOP and if alarm is in progress you see the snooze and dismiss in the main screen of the app - so that you can decide to use the notification or the app to control it…
I have also experimented with the latest new additions on the Wear OS platform announced at this years I/O - doing and ongoing activity for sleep tracking and alarm and also making an Tile. But those features do not work yet on my TicWatch 3 Pro so I did reverted them for the time being and we will test it once the Galaxy Watch 4 is released I guess…
Please let me know any feedback… all your help is very much appreciated…
Many thanks…
Hi folks, I think I did found the problem in automatic sleep tracking and maybe in other scenarios too, so there should be a fix in the latest BETA version.
I will be testing everything this week, but I hope that now we should be getting SPO2 from TW 3 Pro deterministically…
Please let me know…
Hi, my tests seems promising, with the latest Wear OS app and latest Sleep as Android I’m getting SPO2 deterministically in all scenarios including automatic sleep tracking and when HR is enabled in the Wearable settings section in Sleep as Anroid… the only issue remaining is we ar enot able to get HR/HRV and SPO2 at the same time - this is either HRV or SPO2…
Hope it works for you as well…
Yes can confirm the same… Do you think you can find a solution and get all 3 working again?
@gunni on my TW3 I was never able to get HR, HRV and SPO2 at the same time even before the firmware update… have you seen all 3 with a good resolution for the entire night? Can you share screenshot?
To me it seems like there are two modes the LED on the watch back is green and watch is measuring HR and SDNN or the LED is red and the watch is measuring SPO2… It seems to me that the watch is not able to calculate the SDNN from the red LED mode for some reason…
I will experiment if I can make HR and SPO2 working at the same time…
Many thanks…
@petr-urbandroid Ooooh I see… Well, it has worked for me, I will attach screenshots. I will attach some snaps of the latest working captures, but I will say it had become a bit more irregular in its readings right before it stopped working for all 3… Like all of a sudden I was getting crazy high RDI. (But maybe because I don’t always remember to tighten the watch, it’s a bit loose sometimes.
Anyway, it had these issues as well when starting out and I couldn’t understand why it wouldn’t work… I tried enabling/disabling 24 hour tracking on the watch, enabling/disabling the Wearables settings in the Sleep app (Heart rate monitoring/Bluetooth smart and Pulse oximeter Wear OS/Pulse oximeter Bluetooth) and probably tinkering with some more stuff… I think I settled on having everything turned ON on the watch, so all tracking enabled 24 hours and setting the Sleep app wearables to use the Wear OS setting (attached screenshot as well).
Also to your last comment - I can get HR and SPO2 working at the same time? Check the last picture (and notice crazy respiratory analysis… this used to be fine, but changed a couple of weeks ago…)
Actually… Now that I remember. Do you start your sleep manually or automatic? And do you use the phone or the watch to start? I think for this to work I need to start my sleep tracking on the watch!
1 Like
@gunni Looking at the graphs I see that this isn’t a proper HRV tracking, there are ~8-12 values in the HRV chart when the SDNN sensor for some reason took over from the SPO2 sensros during the night… so IMHO it does not make sense to try to enable both to get such a rare data and potentially side effects… Big thanks for the further feedback…
1 Like
I ran into this too with my Ticwatch 3 Pro on the Beta app. Definitely would want to get regular heartrate with SpO2 working consistently. Looking at the HRV data I did get I’m not even sure it’s accurate.
Of the 8 records I’ve made since switching to this watch 6 of them picked up heart rate and SpO2. I never ran into a situation where I got all three.