OnePlus Watch 3: The Battery King of Smartwatches

There’s one programmable button on the bottom right edge, and above it is the digital crown, which also doubles as a configurable button. Last year, you couldn’t scroll the interface by rotating the crown, but that’s now remedied, and there’s some nice haptic feedback as you scroll through. I truly don’t have any qualms about the hardware—it’s IP68-rated and can handle being submersed to about 50 meters (in freshwater). A sapphire crystal protects the bright screen with a new titanium bezel, along with the same stainless steel case. The 22-mm strap is easy to swap.

Performance is buttery smooth, which needs emphasizing because it wasn’t too long ago when basic operations on a Wear OS smartwatch were met with stutters and lag. And all the usual functions work well. I’ve taken calls on the watch, checked notifications, scrolled through my upcoming calendar events, responded to Slack messages, and followed along with navigation while walking.

Health Focus

The biggest improvements, however, are in health and fitness. One of my complaints in my OnePlus Watch 2 review was that the device was “missing health features”, and there were some accuracy issues. It seems as though OnePlus took that to heart. In comparison with the Pixel Watch 3, my heart-rate data was very similar, though I found the OnePlus took longer to show my data than Google’s watch. New features also include an electrocardiogram (ECG), wrist skin temperature sensing, irregular heart-rate notifications, and fall detection.

Unfortunately, bad news for US and Canadian customers: OnePlus says it did not “receive official certification” from the US Food and Drug Administration for the ECG, so that function will not be available in these regions. The company did not explain why the ECG wasn’t cleared in the US, but globally it’s a different story.

Sleep tracking is more accurate now, even picking up the occasional moments when I fall asleep on the couch. I’ve noticed richer data analysis in the OnePlus OHealth app. It extrapolated, for example, that my awake time was somewhat long one night, and that could be impacted by my sleep environment.

I didn’t get much out of the wrist temperature, though this may help women predict periods as my colleague has found using other smart wearables with skin-temperature sensors. I did give the new Vascular Health app a try—it measures arterial stiffness and subsequent risk of cardiovascular disease. Thankfully, my result was “Normal.” You can also get “Low Risk” and “High Risk.” It’s hard to measure the accuracy of this, though I can say for sure that my physician has yet to mention any cardiovascular issues when I visit. Of course, OnePlus is quick to mention that these results are not intended for use in diagnosis or treatment.

One new feature that’s not available yet is 60s Health Check-In. The idea is that within 60 seconds, you can tap your finger on the scan button and get results for six metrics: heart rate, blood oxygen (SpO2), mental wellness, wrist temperature, sleep quality, and vascular age. OnePlus says this will arrive in March.