Fused display up top, fused sensor array below—we won't find anything but broken pieces if we bust this apart, so let's switch on those X-rays from Creative Electron again for a better look.

And here's the (reassembled) pulse oximeter communicating with aliens lighting up in Christmas-y fashion!

Low blood oxygen levels (hypoxemia) can be an indication of COVID-19 or other serious medical issues.

The Apple Watch doesn't track body temp like the Oura Ring 2 does. But while both measurements are informative, neither is meant to provide hospital-grade certainty.

As a reminder, we're not health experts—so read up! Find out more about how blood oxygen tracking works at CNET, or a lot more at the Respiratory Medicine journal.