Apple Watch Ultra 4: Same Look, New Heart
The new Apple Watch Ultra 4 looks identical to its predecessor, but internal upgrades to the chip and health sensors unlock significantly better battery life and deeper fitness insights.
Apple has released the fourth generation of its rugged smartwatch, and the most immediate takeaway is that it looks exactly like the model from last year. There are no changes to the case size, the display dimensions, or the distinctive orange digital crown. For buyers who rely on the watch’s physical durability and outdoor aesthetic, the hardware remains familiar. However, Apple has focused its engineering resources entirely on the internal components, specifically the processor and the array of health sensors that drive the device's daily utility.
According to reporting from 9to5Mac, these internal shifts are designed to address two common complaints about the previous generation: limited processing power and modest battery endurance. By doubling the memory and introducing a new chip, Apple is enabling software features that were previously impossible on the wearable. The result is a device that feels more responsive and offers more granular data, though the lack of visible hardware changes means the upgrade is purely functional rather than stylistic.
Internal Hardware Upgrades
The core of the update is a transition to the S11 chip, replacing the S10 found in the Ultra 3. Apple describes this as its most powerful wearable chip to date, though specific benchmark data is not publicly available. This processing headroom is paired with a doubling of random access memory from 2GB to 4GB. In practical terms, this allows the watch to run more complex background tasks without slowing down, supporting the new software features that rely on real-time data processing.
The trade-off for these internal improvements is that the external interface remains unchanged. Users will not see a larger screen or a new physical button; the value proposition rests entirely on the speed and capability of the silicon inside. For those who prioritize raw performance and software longevity, this is a significant step forward, but for those seeking a visual refresh, the device will be indistinguishable from the 2024 model.
Deeper Health Monitoring
The most substantial change lies in the health sensing system. Apple has introduced a second-generation electrical heart sensor alongside an always-on optical sensor. This combination enables high-frequency background heart rate tracking, providing a more continuous picture of a user's cardiovascular status. Additionally, heart rate variability measurements are now taken up to 24 times more often than before, offering a finer-grained view of stress and recovery levels.
A new feature called Readiness synthesizes data from activity, training load, vitals, and sleep to provide a daily score from 0 to 10. This score comes with a specific recommendation, such as recovering or pushing for performance. While this metric is useful for planning the day, it is an interpretation of data rather than a direct medical measurement. Users must weigh this guidance against their own physical sensations, as the algorithm may not account for every individual variable.
Battery Life Gains
Battery endurance has seen a noticeable improvement, which is critical for a device marketed to outdoor enthusiasts. The Ultra 4 now offers up to 50 hours of standard battery life, an increase from 42 hours on the previous model. In Low Power Mode, the runtime extends to 84 hours. This extra buffer is particularly useful for multi-day hikes or travel where access to charging is limited.
Charging speed has also been enhanced. A 15-minute quick charge now provides 18 hours of runtime, compared to 12 hours on the Ultra 3. This means that in a pinch, the watch can be topped up to last a full day of use rather than just a few hours. However, the charging mechanism itself remains the same magnetic puck, so there is no change in the physical charging process or speed of connection.
