[DigitalToday reporter Hyunwoo Choo (추현우)] Apple unveiled the Apple Watch Ultra 4, a smartwatch for sports enthusiasts and explorers. It features a new health sensing system and the S11 chip, with what it called the most accurate heart-rate measurement among wearables, a readiness score and up to 45 hours of battery life.

The Apple Watch Ultra 4 supports continuous, high-quality health monitoring with a health sensing system that redesigns its optical and electrical heart sensors. In Apple accuracy research involving more than 1,000 people, Apple Watch recorded the highest heart-rate measurement accuracy among major wearable devices. It measures heart rate all day at 5-second intervals using a larger, more power-efficient green LED, and heart-rate variability is measured up to 24 times more often. A new “readiness” score for all types of athletes analyzes activity and training load, vital signs and sleep score, providing a score from 0 to 10 and tailored recommendations such as “recovery needed”, “pace yourself”, “ready” and “peak”.

Battery life has increased sharply. It supports up to 50 hours in daily use and up to 84 hours in low power mode, and a 15-minute charge delivers up to 18 hours. For outdoor workouts, the “endurance workout” mode keeps both GPS and heart-rate measurement on and tracks for up to 25 hours, up 25 percent from the previous model. The “endurance workout (max)” mode maintains 1-second GPS reception and tracks running, walking and hiking for up to 45 hours. That is enough time to finish a 160-km ultramarathon. Apple said the Apple Watch Ultra 4 has the most accurate on-device GPS among sports watches.

It also includes an “audio intelligence” feature using the built-in microphone and the S11 chip. The “sound recognition” feature detects sirens, alarms, doorbells and baby crying even without an iPhone nearby, notifying users who are deaf or hard of hearing. It also integrates Shazam, which automatically recognizes nearby music and displays the song title and artist in the Smart Stack. Apple explained that it processes audio in a dedicated hardware isolation area called “Secure Exclave”, separated from the system, and does not store recordings. Siri AI, provided with watchOS 27, is based on Apple Intelligence and enables personal context understanding and world knowledge to be used from the wrist.

The Apple Watch Ultra 4 will be released in two colors: natural titanium and black titanium. New colors were added to the Trail Loop and Alpine Loop, and the Ocean Band has been remade in translucent silicone in 3 colors. The Apple Watch Hermès Ultra 4 adds a new Grand H titanium band and a new watch face, “Fathom and Wonder”, expressing ocean depth, on natural titanium.

The Apple Watch Ultra 4 starts at 1,249,000 won in South Korea, with preorders starting on the 9th and official sales on the 18th. watchOS 27 will be available from the 14th for Apple Watch Series 9 and later models, SE 3 and Ultra 2 and later models. Siri AI will be offered in beta in English on the same day, with Korean support expected in October.