Sleep tracking mode automatically turns on low power mode. On iPhone too.
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Low Power Mode for Apple Watch Ultra?
- Thread starter msackey
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Just read the new low power mode review on the DC rainmaker blog. Seems pretty useless for workout tracking (running, walking, cycling..) with ~1 minute HR and GPS intervals messing up distance and pacing. It’s a pity that you can’t reduce or even disable the wrist HR, leave GPS in normal (or better) mode and use a chest strap for HR.. I‘d love to see a low power mode dedicated to sports and health with more options to configure and disable ‘regular smartwatch stuff’.
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I think the stack rank of battery drain (other than the screen) is probably the cellular radio, GPS, then HR then O2 sensor. (cell and GPS might be a tie or reversed). WIFI is probably in there somewhere before HR.
For various workouts, it would seem that some change in GPS, HR/O2 sampling would benefit battery and not impact data collection too much.
When I’m hiking, I might be doing 1.25-1.7 mph over various terrain. Sampling GPS and HR less frequently would make sense and not really impair data collection. HR usually samples at every 5 seconds, going to a minute is a big gap so why can’t I just set a sampling rate MYSELF based on activity or interest to say 10 sec or 15 secs, that would reduce sampling rate by half or more, saving battery etc.
Same with GPS, if I’m hiking and not covering too much distance too quickly, reducing GPS sample rate to 1/2/5 minutes might be fine, but if I’m running or walking, that level of latency in the data will certainly produce errors in aggregate collection and accuracy. Why they simply don’t offer something USER selectable or more specific to an activity is beyond me.
Give it a day to settle down. After the update, it does some sort of number crunching behind the scenes for some time, and that sucks down the battery. With an older watch, leave it on the charger overnight.
You shouldn’t need to do a backup / restore; just give it a day.
(Not defending Apple! There really should be a way for them to fix this. Just suggesting that waiting it out is enough, and, annoying as it is, isn’t as annoying as a backup / restore.)
This still persists with the Ultra. I wasn’t adversely affected by it; the battery is HUGE by my standards, and the whole “put it on the charger to update” thing left me with my normal end-of-day charge anyway. But it definitely would have been well below normal (though still more than plenty) without having been on the charger during the update.
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I believe when you are using chest strap HR that is connected to the Watch, the built-in wrist HR is off. I'm pretty sure of that. I typically use a Polar H10 heart rate monitor (chest strip connected via bluetooth) to my Ultra to go running because the wrist HR is typically not very accurate the first several minutes of a run when my wrist is cold.
Yeah first day I got my AWU battery dropped pretty fast. Second day significantly better. Third - it’s sipping. Lol.
Thanks! Didn’t realize that. In that case it’s a bit useful for walking/hiking, but less useful for road cycling and not so much for mountain biking. It’s not a real issue for me t.b.h, I don’t mind packing a small power bank or charging it on the road via my hub dynamo. It would still be nice though to have a lower power mode with more workout data if this can be achieved by disabling more generic smartwatch functions.
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I agree. It would be nice to have a mode to quickly turn off all functions that are strictly smartwatch related that are unrelated to workouts such as notifications, cell signal, and the likes.
I used to have a heart rate monitor that I used with my AW3 thinking it was better. But every workout, it always put in 1-2 3000bmp+ values - and I'd have to manually scroll through the heart rate values and remove it. That got old pretty quick. I forget what brand it was lol. But yes, it did turn off the AW's heart rate sensor during the workout. But for the AW 3 it was a noticeable battery saver. 
Oh that's awful!I used to have a heart rate monitor that I used with my AW3 thinking it was better. But every workout, it always put in 1-2 3000bmp+ values - and I'd have to manually scroll through the heart rate values and remove it. That got old pretty quick. I forget what brand it was lol. But yes, it did turn off the AW's heart rate sensor during the workout. But for the AW 3 it was a noticeable battery saver.
I highly recommend the Polar H10 heart rate monitor. It's reliable and accurate. It also provides much more readings per time period than does the built-in wrist monitor. This is clearly visible in the plotted HR graph. And indeed, it does save overall battery life for the watch.
What is the difference between AW and AWU low power mode ?
Both currently expand the battery when enabled but what is the AWU new low power mode going to bring ?
My understanding is the "other" low power mode for AWU is activated in Settings > Workout and reduces the frequency of heart rate monitoring and GPS tracking.
It's a good question. Pretty underwhelming in my opinion. Having said that if I was using it for ultra marathons or triathlons I might have a different opinion