Battery Saver Mode Updates:
This update extends your battery life even further by turning on Battery Saver to only display the time once your battery falls below 10%.
Improved Off Body Efficiency:
After 30 minutes of inactivity your watch will go into deep sleep mode to conserve battery.
Smart App Resume for all Apps:
You can now easily pick up where you left off across all apps on your watch.
Two Step Power Off:
You can now turn off your watch in two easy steps. To turn off your watch, simply hold the power button until you see the power off screen and then select 'power off' or 'restart'
In recent years, Wear OS watches have featured both an application processor (AP) and the low-power co-processor, or microcontroller unit (MCU), for what Google calls a “dual-chipset architecture.”
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looking at a Calendar alert in the notification feed keeps you on the MCU. Tapping to open the full Google Calendar Wear OS app triggers the AP.
“Pixel Watch uses a combination of on-device machine learning and deep optimization, down to the processor level, to give you an accurate measurement of your heart rate continuously at once per second.” As a reminder, that’s the Exynos 9110 SoC and a Cortex M33 co-processor.