Two Smart Rings, One Caliper, a Lot of Squinting

TEARDOWN // You cannot really open a smart ring without ruining it, so this is a non-destructive bench session: calipers, a jeweller's loupe, and the published sensor specs held up against what the apps actually report.

The Oura Gen3 is the elder statesman here, reading sleep and recovery off the finger but gating most of the good stuff behind a $5.99 monthly membership, which still irritates me on hardware I have already paid for. Samsung's ring undercuts that by simply not charging a subscription for the core readings.

Physically they are astonishingly similar, a battery wrapped in a curve of sensors and a lot of clever potting. The interesting fight is not the hardware, which has basically converged, but the business model wrapped around it. On the bench they are twins. In your account they are not.