No sleep score, no steps: this Signal smart ring from an ex-Google head is focused on cracking cuffless, calibration-less blood pressure readings

Blood pressure has long been considered the "holy grail" of PPG-powered wearable tech. Because (up until now) you really need an inflatable cuff to measure, or at least to calibrate, blood pressure readings, and that's been difficult to do with a smartwatch alone.

The Huawei Watch D series incorporated a cuff into the smartwatch itself, while Apple has introduced its Hypertension Detection feature, which earmarks possible hypertension after 30 days of using an Apple Watch, but doesn't actually provide blood pressure readings. No LED-based device has really been able to crack it. Until now, apparently.

The Signal Ring is the brainchild of Tom Moss, an ex-head of Android at Google who's founded several companies since leaving Google and co-founded several other companies, including drone business Skydio, which eventually ended up being bought by Razr.

Signal is a smart ring with a difference: rather than provide lots of different metrics...

Copyright of this story solely belongs to techradar.com. To see the full text click HERE