Apple just announced a major update for the Apple Watch and the Health app on iPhone, focused on more accurate health measurement and using AI to translate complex numbers into something easy to understand. Let's look at what's new, and how useful it really is.
A more accurate heart sensor that measures more often
The Apple Watch Series 12 and Apple Watch Ultra 4 come with a new heart sensor, both optical (light-based) and electrical, which Apple says is the most accurate of any smartwatch right now, tested against a sample of over 1,000 people compared with other watch brands.
The clear change is measurement frequency:
• Heart rate: measured every 5 seconds, all day (previously at much wider intervals)
• HRV (Heart Rate Variability), a measure of the body's stress and recovery, is now measured up to 24x more often — every 5 minutes
Why does this matter? The more often it measures, the faster you can see changes in your body — like noticing you're stressed or under-rested before you even feel it yourself.
Apple also splits HRV into 2 types: Recovery HRV — day-to-day stress and recovery signals; and Overall HRV — a long-term health picture, including cardiovascular health. The simple principle: higher variability usually means the body is recovering better.
"Readiness Score": a number telling you how ready your body is today
A new feature called Readiness looks at your activity data, various heart values, and sleep score, then sums it into a 0-10 score with 4 simple recommendations:
1. Recover — rest first
2. Pace Yourself — take it easy, don't overdo it
3. Ready — ready for your normal routine
4. Go For It — your body is fully ready today
The score also updates during the day — for example, it changes after a hard workout. The system was developed using data from the Apple Heart and Movement Study, a long-running research project Apple runs with sports scientists and doctors.
A redesigned Health app that uses AI to read the data for you
The highlight of the new Health app (arriving with iOS 27 later this year) is using Apple Intelligence, Apple's AI system, to translate complex health numbers into something easier to read. It's split into 2 main tabs:
The Insights tab — everything summarized on one page: it brings together heart, sleep, readiness, fitness, and cycle data in one easy view, plus a "For You" section suggesting things to adjust — for example, if you've stayed up late several nights running, the app might suggest tweaking your bedtime routine.
The Longevity tab — a long-term view of your health: it looks at historical data to assess heart health, sleep, mental health, movement, metabolism, hearing, and nutrition. The highlight is Health Age, a feature that calculates how your "health age" compares with your actual age, using Apple Watch data like VO2 max (your body's ability to use oxygen, a measure of heart and lung fitness), resting heart rate, sleep, and HRV. It can also factor in lab results like A1c (average blood sugar) and LDL (bad cholesterol).
Assess your body at home, no clinic needed
Another interesting feature is Movement Evaluations, letting you assess flexibility, strength, balance, and VO2 max at home, using the iPhone camera together with the Apple Watch.
The upside Apple emphasizes: everything is processed on-device, with no video recorded or sent anywhere — the privacy angle matters here, because this kind of assessment normally requires seeing a physical therapist or fitness specialist.
Book lab tests through the app
US users will be able to book 50+ lab tests directly through the Health app for US $119 (roughly 4,000+ baht) at around 2,000 Quest Diagnostics locations across the US — there's no word yet on when it'll expand to other countries.
More support for women's life transitions
The Cycle Tracking feature adds support for perimenopause and menopause. Users can log which phase they're in so the app can adjust its symptom tracking accordingly.
Notably, users aged 40 and up get a notification if their logged cycle patterns suggest perimenopause, so they can consult a doctor right away — many people don't realize they've entered this phase, since symptoms can start years before menopause itself. And if there's bleeding after menopause, the app also alerts you to see a doctor immediately.
Other things in the update
• Workout Buddy (an AI voice coach during workouts) works even without an iPhone nearby, and now supports Spanish in addition to English
• GymKit connects with AirPods Pro 3, sending heart data to supported gym treadmills or bikes
• A new machine learning model makes treadmill distance measurement more accurate from the first step
Verdict: how excited should you be?
These features sound interesting, but keep in mind:
• You need an Apple Watch Series 12 or Ultra 4 to get the new heart sensor — older models won't get this feature
• The redesigned Health app has to wait until late this year, and requires an iPhone/iPad that supports Apple Intelligence
• Health Age needs an Apple Watch; VO2 max measurement needs an Apple Watch, AirPods Pro 3, or a supported third-party heart sensor
• Some features (like booking lab tests) are still US-only at first
• The Vitals app is for general wellness only — not a medical device — and Cycle Tracking shouldn't be used as birth control
watchOS 27 starts rolling out September 14, for Apple Watch Series 9 and up, SE 3, and Ultra 2 and up (must be paired with an iPhone 11 or newer running iOS 27).
