Apple Watch Ultra 4 Review: A Powerhouse for Health Tracking
Longer battery life and advanced heart monitoring redefine fitness wearables.
1Incremental hardware upgrades
The Apple Watch Ultra 4 maintains the same titanium case design and color options as its predecessor, with only three key upgrades: the new S11 chip, improved battery life (50 hours normal use, 84 hours in Low Power Mode), and a second-generation heart monitoring system. While the exterior remains unchanged, the 49mm titanium case with 3,000-nit OLED display continues to set the standard for rugged smartwatch design. The lack of visual updates is offset by the device's proven durability and premium build quality that competitors still struggle to match.
2Game-changing battery performance
Apple addresses the biggest pain point for athletes with significantly improved battery life - now capable of lasting through an Ironman race at 18 hours in workout mode. Real-world testing showed 81% battery remaining after a full day including an hour-long workout. The 45-minute fast charging to 80% eliminates typical smartwatch charging anxiety. This makes the Ultra 4 the first Apple Watch truly suitable for multi-day adventures without requiring daily charging, a critical upgrade for endurance athletes and travelers alike.
3Revolutionary heart monitoring
The new Health Sensing System combines optical and electrical sensors to measure heart rate more frequently throughout the day, enabling more accurate HRV (heart rate variability) calculations for stress tracking. Apple cites scientific studies showing this system outperforms all current wearables. The sensors automatically adjust frequency in Sleep or Theater modes to prevent light disturbance. New metrics like post-workout heart rate recovery provide athletes with granular performance data previously only available from medical-grade devices.
4WatchOS 27's smart features
The new Siri Modular watch face dynamically displays the most relevant Smart Stack widget in its center complication. While only one new face was added, the larger Ultra 4 display shows additional information with optional Ultra font. The watch runs on the new S11 chip with 4-core Neural Engine, enabling future AI features like Live Rewind and Siri Recap. Current available features include enhanced Shazam music recognition that identified even obscure YouTube remixes instantly during testing.
5Upcoming AI capabilities
Two notable AI features - Live Rewind (15-second audio recap) and Siri Recap (daily summary) - will launch later in 2024, currently undergoing privacy reviews especially in strict European markets. These opt-in features process audio locally without storage, displaying visible indicators when active. The new Sound Recognition helps hearing-impaired users identify important sounds like sirens or doorbells. Apple emphasizes all processing happens on-device, though the always-listening functionality may raise privacy concerns for some users.
6Health app integration
All collected health data feeds into the redesigned iOS Health app (currently in developer beta), offering clearer visualization of sleep quality, fitness levels, and vital signs. The new system enables comprehensive readiness scores after one week of data collection, though this feature wasn't available during initial testing. The integration creates a holistic health monitoring ecosystem that goes beyond typical fitness tracking, potentially offering medical-grade insights for preventive healthcare.
7Band options refresh
While the watch itself looks identical, Apple introduced multiple new band options across all styles including Sport, Nike, and Hermès collections. The Translucent Gray Ocean Band emerged as a standout pairing with the Natural Titanium case during testing. These accessories provide the primary avenue for personalization since the core device design remains unchanged. The wide selection ensures compatibility with both athletic and formal wear, maintaining the Ultra's versatility across different usage scenarios.
8Precision fitness tracking
Apple claims the Ultra 4 offers the most accurate step counting of any smartwatch, though initial testing showed slightly lower counts than previous models. The new Steps complication displays real-time progress directly on watch faces. Outdoor workout mode now lasts 18 hours on a single charge. Combined with the improved heart rate monitoring, these upgrades position the Ultra 4 as a legitimate training tool rather than just a fitness tracker, capable of providing data serious athletes can trust for performance analysis.
9Who should upgrade?
The Ultra 4 represents an evolutionary rather than revolutionary update. Casual users with Ultra 2 or 3 models won't find compelling reasons to upgrade unless they need the enhanced battery life. However, endurance athletes and health-focused users benefit significantly from the medical-grade heart monitoring and multi-day battery. The watch's true value emerges when used as part of Apple's expanding health ecosystem, particularly with the upcoming Health app redesign and AI features that could redefine personal health monitoring.
Original article: Mashable — Apple Watch Ultra 4 Review: A Powerhouse for Health Tracking