The Apple Watch Ultra's battery life sounds great — but there's a catch

Product shots from end of Apple Event
(Image credit: Apple via YouTube)

One of the bigger announcements at yesterday's Apple event was the launch of the Apple Watch Ultra, a bigger, beefier smartwatch that has a number of features, including a dive computer, emergency siren, redesigned compass app, and more. But what caught my attention was its rated battery life of 36 hours — double that of every Apple Watch to date, and much longer than most of the best smartwatches.

In all my years of testing smartwatches and fitness trackers, one of the features I value the most is battery life. It's a real pain to have to remember to plug in a smartwatch every night to make sure it's ready to go the next morning. And, for as long as I've been testing smartwatches, most can't make it past a day. 

Sure, the new Samsung Galaxy Watch 5 has the ability to charge up to 50 percent in half an hour, but a watch's endurance should be measured in days, rather than hours. It's one reason why I tend to gravitate towards Garmin watches, such as the Epix 2 or Forerunner 245. They don't have as many features as the Apple Watch when it comes to making calls, responding to texts — and a host of other things — but I don't have to worry that, if I forget to plug it in at night, I'll have a useless hunk of metal the next day.

So, while the Apple Watch Ultra's 36 hours isn't nearly as long as the 16 days of the Epix 2, it's an improvement over previous models. 

However, it's worth reading the fine print — those 36 hours are likely to be much less, depending how you use the Apple Watch Ultra. 

On Apple's page for the Ultra, it states that the 36 hours is based on "180 time checks, 180 notifications, 90 minutes of app use, and a 60-minute workout with music playback from Apple Watch via Bluetooth, over the course of 36 hours; Apple Watch Ultra (GPS + Cellular) usage includes a total of 8 hours of LTE connection and 28 hours of connection to iPhone via Bluetooth over the course of 36 hours."

So, that figure does not necessarily include active GPS use, which I've found to chew up battery life faster than a puppy with your favorite shoe. Though Garmin says the Epix 2 will last up to 16 days, that figure drops to 30 hours when using GPS, and just 9 hours when using music and GPS. 

Don't get me wrong — I'm pleased that the Ultra is getting a longer battery life than other Apple Watches. I just think it's going to be a lot shorter for those who want to use it for more active endeavors. 

Mike Prospero
U.S. Editor-in-Chief, Tom's Guide

Michael A. Prospero is the U.S. Editor-in-Chief for Tom’s Guide. He oversees all evergreen content and oversees the Homes, Smart Home, and Fitness/Wearables categories for the site. In his spare time, he also tests out the latest drones, electric scooters, and smart home gadgets, such as video doorbells. Before his tenure at Tom's Guide, he was the Reviews Editor for Laptop Magazine, a reporter at Fast Company, the Times of Trenton, and, many eons back, an intern at George magazine. He received his undergraduate degree from Boston College, where he worked on the campus newspaper The Heights, and then attended the Columbia University school of Journalism. When he’s not testing out the latest running watch, electric scooter, or skiing or training for a marathon, he’s probably using the latest sous vide machine, smoker, or pizza oven, to the delight — or chagrin — of his family.

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