I tested the Whoop 4.0 and it might be the best fitness tracker out there - I tested the latest model and was surprised at ...

At first glance, the Whoop might look like a bracelet (or sporty ... you might not want to deal with a sweaty strap tucked under your sports bra. On the other hand, smart rings, worn on your ...

However, Whoop’s insights are slightly more detailed. The photodiodes on the underside of the strap stay pressed against your skin and track heart activity and breathing patterns to create ...