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Apple Watch Series 12 and Ultra 4 launch and AI features

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2026-09-11 16:17 UTC → 2026-09-11 20:57 UTC · added ~~removed~~

Following the ‘Surprise and Shine’ keynote on September 9, 2026, Apple has detailed the capabilities of the Apple Watch Series 12 and Apple Watch Ultra 4. Both models utilize the new S11 chip and run watchOS 27. The hardware features a redesigned Health Sensing System with larger, more efficient LEDs and expanded electrode surface areas to improve biometric accuracy. Key health enhancements include heart rate measurements taken every five seconds—60 times more frequent than previous models—and a 24-fold increase in heart rate variability (HRV) sampling. New software metrics include a ‘health age’ and a ‘Readiness’ score, which provides a daily 0–10 rating based on sleep, training load, and vitals to recommend activity levels. The Apple Health app is also undergoing a major redesign, which includes the introduction of a ‘Longevity’ tab. This redesigned app will use Apple Intelligence to provide personalized insights by integrating data from smartwatches and smartphones, covering metrics such as metabolic health, hearing, and nutrition. Users can also manually add laboratory results, such as cholesterol and blood glucose tests. Furthermore, Apple is introducing AI-driven physical assessments that utilize smartphone cameras and watches to evaluate flexibility, strength, balance, and movement patterns. The Ultra 4 specifically offers extended battery life, with reports citing up to 50 hours of runtime and a specialized ‘Extended Workout mode’ providing up to 45 hours of tracking. In low power mode, the Ultra 4 can reach up to 84 hours. The Series 12 will be available in aluminum, titanium, and ceramic finishes. Apple is also introducing ‘Audio Intelligence’ features powered by Apple Intelligence, including ‘Siri Recap’—which generates high-level summaries of conversations—and ‘Live Rewind’, which allows users to view text snippets of the last 15 seconds of audio. Apple asserts that audio is not recorded or stored, stating that data is processed on-device or via Private Cloud Compute in a secure, isolated hardware compartment to ensure privacy. Retail availability for the new models is scheduled to begin on September 18, 2026.

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