The Apple Watch Ultra can now last even longer on a single charge. In watchOS 9.1, Apple has added a workout setting that extends battery life to an estimated 60 hours by reducing GPS and heart rate readings.
Battery life estimates for the Ultra can be a little tough to parse. The official line is that the watch lasts up to 36 hours with normal use and up to 12 hours during an outdoor run. However, Apple also introduced a Low Power Mode in watchOS 9 that limits or disables certain features to last enough to finish an Ironman race — roughly 14-15 hours. But to get that 60-hour estimate, you have to enable both Low Power Mode and the new “Fewer GPS and heart rate readings” setting.
The vanilla Low Power Mode turns off the always-on display and limits background features and sensor readings like auto-workout detection and irregular heart rate notifications. And while you can use cellular features on demand, it’ll only fetch updates about once an hour. Otherwise, continuous heart rate and GPS readings are left untouched when you’re working out. The Low Power Workout Mode, however, reduces how often the Ultra takes those heart rate and GPS readings as well. Instead, you’ll only get heart rate readings once per minute, while GPS readings will be reduced to once every two minutes.
As pointed out by tech reviewer DC Rainmaker, enabling this setting means your workout data won’t be quite as in-depth. For example, you won’t get real-time pace or distance on the wrist or advanced running metrics. Your GPS map also won’t be as accurate.
To enable the new setting, you’ll have to first update to watchOS 9.1. Once that’s done, go to Settings > Workout > Fewer GPS and heart rate readings. Like Low Power Mode, this setting can also be used with any watch that supports watchOS 9.
That 60-hour estimate, however, is based on Apple’s own specific testing scenario for the Ultra. What you’ll actually get in real life may differ depending on your usage. Your mileage will also vary if you use this setting on a Series 8, second-gen SE, or an older Series model. For example, although the Ultra is rated for 36 hours with normal use, I regularly get around 48-50 hours. Once, during a lazy weekend, I got up to 60 hours with no battery-saving features enabled. It’s possible that Apple’s 60-hour estimate with these settings enabled may also be conservative.