The ring is inscribed with "Benedictus XVI"—the Pope's title in Latin—and features an image of St. Peter. Pope Benedict XVI shows his Fisherman's Ring.

First, the Oura Ring 4 replaces the 3’s bulbous sensors with recessed ones for a more comfortable fit. The interior of the Ring 4 is also made from titanium for added durability and sleeker wear.

As tradition dictates, the late pontiff’s signet ring will be destroyed — or defaced, at least — within the walls of the Vatican following his death on Easter Monday.

As wearable technology, like the Oura Ring, becomes more ubiquitous, some users say having so much data about their bodies is making them more anxious. As wearable technology, like the Oura Ring ...