Oura Ring 4 promises 'most accurate' health monitoring

The Oura Ring 4 is now official, and it brings a handful of improvements over its predecessor. One of these improvements is a slimmer design. The new smart ring is made fully of titanium, while the previous offering had an epoxy interior. It also has no flat edges and is completely round.

Another noticeable design change is the recessed sensors. On the Ring 3, they had dome-shaped covers, and with the sensors being recessed, the interior of the new smart ring is now flatter, contributing to better comfort. Speaking of the sensors, they've seen an upgrade too.

Oura says that the sensors of the Ring 4 deliver the "most accurate" reading of different biometrics. More specifically, the company touts that it is more precise in offering heart rate readings, with 7% fewer gaps in the daytime graph. The smart ring is also said to be 120% better at sensing SpO2, with 30% improved accuracy in overnight measurement.

Then, there's an improvement in automatic activity detection, which now supports heart rate zones for over 40 activities. The Oura Ring 4 also comes with an updated algorithm. It can access more signal pathways from the finger for an optimized reading.

Other upgrades introduced with the Oura Ring 4 include a better battery life, rated at up to eight days. There are new sizes as well. You can get one from size 4 to size 15. Lastly, it comes with a new charging dock, which is now a bit sleeker than the one that came with Ring 3 (Horizon curr. $299 on Amazon). The new smart ring has a starting price of $349, and its subscription is $5.99 per month.