Apple on Tuesday introduced the Apple Watch Ultra 4, a rugged sports watch that combines a redesigned Health Sensing System with the new S11 chip to deliver higher‑frequency heart monitoring, expanded fitness metrics, and extended battery life, Apple said.
The company said the device now measures optical heart rate every five seconds and samples heart rate variability far more often than prior models. Apple said it redesigned the optical and electrical sensors and validated the new heart rate accuracy in a study of more than 1,000 participants, finding the Ultra 4 had the highest accuracy among leading wearables in that test.
Apple also introduced a readiness score that gives a daily 0‑10 assessment of a user’s capacity to train or recover. The score combines recent activity, training load, vitals, and sleep data and updates as new measurements arrive. Apple said the readiness algorithm was developed using data from the Apple Heart and Movement Study with input from exercise scientists and physicians.
The S11 chip powers both the sensing and expanded on‑device features. Apple said the watch now records overnight vitals that include a recovery HRV metric analyzed against a personal baseline, and offers a daytime vitals view to surface shifts earlier in the day. The pedometer has been reworked with machine learning and the S11 chip to improve step and distance accuracy, and a new Steps complication places step count on the watch face.
Battery life improved substantially, Apple said. For everyday use Ultra 4 delivers more than two days and up to 50 hours, with a Low Power Mode extending life further. For workouts, Apple described an Extended Workout mode that supports up to 25 hours with full GPS and heart rate, and a Max Extended Workout mode capable of tracking up to 45 hours while still taking GPS readings every second.
AI Features Privacy Materials And Availability
Apple positioned the Ultra 4 as a platform for new audio and AI features. Audio Intelligence functions include Live Rewind to review the prior 15 seconds of ambient speech, Siri Recap to generate short high‑level summaries, and Sound Recognition to alert users to important sounds. Apple said these features process audio inside a Secure Enclave on the S11 and do not create or store raw audio recordings.
Apple also said watchOS 27 brings Siri AI to the wrist, enabling more contextual voice interactions. Some AI features will arrive in beta first and require an Apple Intelligence‑enabled iPhone for full functionality, Apple said. The company cautioned that certain server‑side features will be subject to daily usage limits and regional availability restrictions.
On design and sustainability, Ultra 4 is offered in natural and black titanium. Apple said the device uses 45 percent recycled material by mass, including 100 percent recycled titanium for the 3D‑printed case and 100 percent recycled cobalt in the battery. Bands include updated Trail Loop, Alpine Loop, and translucent Ocean Band colors, and a Hermès Ultra 4 edition offers a Grand H titanium band with an extension mechanism.
Apple said the Apple Watch Ultra 4 is available to pre‑order now with wider retail availability to follow. Pricing starts at $799 in the US. The company also highlighted new Health app features on iPhone, optional lab testing purchases, and expanded fitness functionality tied to watchOS and Apple Intelligence.
