Oura Ring 4 for $349: While the Ring 5 is the smallest smart ring on the market, the Ring 4 is still slimmer and lighter than its predecessor. AccordionItemContainerButton LargeChevron You can wear your smart ring on any finger, but most manufacturers recommend wearing these gadgets on your index finger for the best accuracy, though the middle or ring finger can also work. AccordionItemContainerButton LargeChevron Choosing the best smart ring for you comes down to a few key considerations: Biometric tracking: At a minimum, it's worth looking for essentials like continuous heart rate monitoring, sleep tracking accuracy, and daily activity tracking, all of which are pretty common across most modern models.