Question 1

Does Series 12 have a bigger battery than Series 11?

Accepted Answer

Everyday battery life is unchanged at 24 hours. Low Power Mode rises to 38 hours. The outdoor workout figure rises to 10 hours from 8, and a 15-minute charge now delivers 12 hours of use, up from 8 hours on Series 11.

Question 2

What is the Health Sensing System?

Accepted Answer

The Health Sensing System is a redesigned optical and electrical heart sensor on Series 12. The old design used four circular photodiode windows; the new design uses eight windows with double photodiodes in each. ECG electrode surface area increased by 24%; background heart rate switched from infrared to green LEDs and now samples every 5 seconds. HRV is measured up to 24 times more frequently, and Series 12 surfaces RMSSD alongside SDNN in Apple&#8217;s own app for the first time; both have always been derivable from the underlying data via HealthKit. Apple uses RMSSD for Recovery HRV and SDNN for its other HRV measurements.

Question 3

What is the Readiness app?

Accepted Answer

Readiness analyses recent activity, training load, vitals and sleep to produce a daily 0–10 score with a recommendation: Recover, Pace Yourself, Ready, or Go For It. It updates throughout the day and requires Apple Watch Series 12 or Ultra 4.

Tag: Series 12

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