A power saving mode which reduces the amount of heart rate readings and GPS polling can extend its battery life to around 60 hours.

[6][7][8] In December 2023, Apple Watch Series 9 and Ultra 2 were temporarily pulled from the U.S. market due to patent litigation by Masimo.

[10] Victoria Song of The Verge felt that the first-generation Apple Watch Ultra was "a great first attempt at a rugged smartwatch" and "legitimately good for weekend warriors and intermediate athletes", noting features such as the Action button (which she believed should be added to the main Apple Watch line as well) and multi-band GPS, and the larger screen being easier to read.

She noted that Apple's battery life estimations were conservative in comparison to real-world use, where she regularly got closer to 48 hours of battery life during regular exercise use without using power saving modes, and another Verge staff member reported 56 hours via general, non-fitness use at home.

However, she noted that the Apple Watch line still lacked certain features (including longer battery life, offline maps and trail navigation, and transflective displays) and fitness metrics in comparison to competitors such as Garmin and Polar, but that watchOS still "runs circles around fitness watches in terms of connectivity and simplicity".