The Quantified Scientist tested the Apple Watch Series 12's revamped heart rate sensor against a Polar H10 ECG chest strap across indoor cycling, running, and weightlifting. The Series 12 performed very well with correlations of 1.0, 0.98, and 0.97 respectively, placing it above 85% of competing devices during weightlifting.
Apple released the Watch Series 12 and Ultra 4 with iterative improvements including a new more powerful chip and improved health sensors. The most notable change is the return of ceramic as a case material in Pearl White and Night Blue shades, featuring enhanced durability through improved manufacturing processes and a cleaner design without red crown accents.
Apple's iPhone 18 Pro, iPhone 18 Pro Max, Apple Watch Series 12, Apple Watch Ultra 4, and AirPods 5 began shipping to customers on September 18 in Australia and New Zealand. The devices are rolling out globally across Asia, the Middle East, Europe, and North America, with availability through Apple Stores, carriers, and retailers like Target, Walmart, and Best Buy.