Apple Watch Ultra 4 Extends Battery to 50 Hours, Adds New Heart Rate System
Updated
Updated · Mashable · Sep 17
Apple Watch Ultra 4 Extends Battery to 50 Hours, Adds New Heart Rate System
3 articles · Updated · Mashable · Sep 17
Summary
Up to 50 hours of normal use and 84 hours in Low Power Mode mark the biggest practical upgrade in Apple Watch Ultra 4, with the reviewer charging it roughly every third day.
A new second-generation optical and electrical heart sensing system is the main hardware change, enabling more frequent readings, finer health data and a forthcoming Readiness score after a week of use.
Most other hardware stays nearly unchanged from Ultra 3 — the 49mm titanium design, 3,000-nit display and core functionality are largely the same, with the S11 chip powering the update.
Several headline software features are still incomplete: Live Rewind and Siri Recap arrive later this year, while Europe may wait longer because of privacy rules and the redesigned Health app is only in iOS 27 beta.
For buyers, the review frames Ultra 4 as a meaningful upgrade mainly for endurance athletes who want stronger battery life and more precise heart-rate tracking, while casual users can keep older Ultra models.