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Hilo Core is a wrist band that tracks blood pressure with optical sensors and reports to an in-depth smartphone app. It’s now launching in t...

The $399 Signal Ring by Vital Signals claims to deliver cuffless, calibration-free blood pressure readings from the finger.

One excels at fitness, the other at sleep. After extensive testing, here's what you need to know about these smart health tracking devices.

I tested them against the Apple Watch and the Polar chest strap to find out whether you can trust them for your workouts.