I ran a half marathon with the Apple Watch Ultra 4 and Samsung Galaxy Watch Ultra 2 — here's the one that came out on top

If you’re looking for a smartwatch that’ll double up as a sports watch for your next race, you’re probably choosing between the Apple Watch Ultra 4 and the Samsung Galaxy Watch Ultra 2. We’ve reviewed both on Tom’s Guide, but to find out more, I strapped both to my wrist and ran a half marathon — read on to see which came out on top.

When deciding between the two, note that the Apple Watch Ultra 4 requires an iPhone, while the Galaxy Watch Ultra 2 works only with Android or Galaxy.

Both have a large case — 49mm for the Apple Watch Ultra 4 and 47mm for the Samsung Galaxy Watch Ultra 2. Both have built-in GPS and track your sleep, stress, workouts, recovery, and more. The Apple Watch Ultra 4 costs $799, whereas the Samsung Galaxy Watch Ultra 2 is $699. But which is most accurate? Let’s find out.

I ran a half marathon with the Apple Watch Ultra 4 and Samsung Galaxy Watch Ultra 2: Here’s which came out on top

GPS

Let’s start with the basics — if you’re wearing a watch to track a race, you want it to track your GPS pretty perfectly. When putting both devices side by side, the GPS is pretty much spot on for both, and this shows when comparing the recordings to the actual map of the course.

With both watches, I had auto-lap set up, and both were pretty much hitting the distance markers at the right point. Of course, both watches recorded a slightly longer distance than the actual race itself, but this accounts for weaving runners and not ever really being able to stick to the race line. The Apple Watch Ultra 4 recorded the run as 13.23 miles; the Samsung Galaxy Watch 2 recorded it as 13.21 miles.

Heart rate

I didn’t wear a chest strap with the two watches, so I’ll use my Oura Ring 5 as my baseline. According to my Oura Ring 5, my average heart rate was 163 beats per minute, with most of my time spent in zones 4 and 5, showing I was pushing myself throughout the run.

The heart rate graphs on the Apple Watch Ultra 4 and Samsung Galaxy Watch Ultra 2 also look pretty similar, with my average heart rate on my Apple Watch recorded as 159 beats per minute and my Galaxy Watch recorded as 160 beats per minute.

Again, this one is pretty much too close to call.

Elevation

One thing that my colleague, Dan Bracaglia, found when testing the Samsung Galaxy Watch Ultra 2 was that the elevation gain seemed inaccurate during his runs and rides. I didn’t find the same — the official course route has a total elevation gain of 311 feet, and my watch recorded the run as 342 feet. Similar to GPS, a small difference is often down to altimeter sensitivity, GPS drift, or weaving through runners on the course.

Comfort and usability

I’m a pretty petite runner, and both watches felt pretty chunky on the wrist. Design-wise, the Samsung Galaxy Watch Ultra 2 felt a little wider, but it doesn’t have much in it.

Both have those all-important physical buttons that make using the watch with sweaty fingers a little bit easier, and both have bright, beautiful screens that were easy to see, even in direct sunlight. You do see slightly more on the screen of the Apple Watch Ultra 4, which is bigger, but again, there’s not a lot in it.

Which should you buy?

The answer really depends on whether you’re team iOS or Android. If you have an iPhone, don’t buy the Galaxy Watch Ultra 2, as it won’t work with your phone. Both are like having an extension of your phone on your wrist, with tonnes of apps at your fingertips.

Both did a stellar job of recording my half marathon, and both are probably the top contenders if you want a smartwatch with the capabilities (but sadly not the battery life) of a sports watch.

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