Every new major firmware update causes something in the back of my mind to worry about the effects the software might have on battery life, even just a little. In my experience, Samsung's done a great job in recent years to eliminate those worries, but they still creep up now and again, likely due to old memories.
I went through a similar phase when I recently received the One UI 6 Watch update on my 44mm Galaxy Watch 5, but I'm happy to say that nothing has changed.
A screenshot showing battery usage on the Galaxy Watch 5 (1 days 21 hours since last full charge)
A screenshot showing the estimated battery life left on the Galaxy Watch 5 (1 day).
My Galaxy Watch 5's battery life rocks, even after One UI 6 Watch. I still get somewhere close to three days on a full charge while wearing my Watch day and night — and no less than two days, at the very least.
Except for period prediction, I keep every health and fitness feature continuously on. I also use the new Double Pinch gesture.
If you're wondering how I achieve these figures, it only takes a little bit of active management. I only use AOD (Always on Display) on occasion, and I only use Location when my Watch isn't connected to my phone.
Here's a more detailed article we wrote about the importance of managing AOD and Location on the Galaxy Watch.
Furthermore, I keep Wi-Fi almost always off. Unless I'm somewhere far away from my phone and need to access the internet on my Galaxy Watch — which virtually never happens — there's no need for Wi-Fi to be kept on.
There are many misconceptions about the importance of Wi-Fi on Galaxy Watches, so I recommend hitting that link and checking out that in-depth explanation of how it all really works. You might get better battery life from your Galaxy Watch and feel way more comfortable keeping Wi-Fi off.
In any case, I'm happy to see that the One UI 6 Watch update hasn't had a negative effect on my smartwatch. I have no second thoughts recommending it. Battery life is as good as ever, the new features are welcomed, and even the UI feels snappier. Good times!