While the physical mechanics of the sensing would involve scanners familiar to users — based in the back of the phone or with active monitor on the back of the case of a smartwatch — a lot of the work will come into the software processing the data. The blood flow data would be used to generate a waveform pattern for the authentication application that must be matched.
The match, however, will vary with different extremes in blood pressure. Standard deviations and algorithms will take account for diastolic and systolic peaks. Ultimately, though, it’s more sensitive metric that’s based on relatively anonymous data — the app can be tuned to match for a certain threshold of accuracy to the master pattern.
At the end of the day, the company does not have to bring this technology out to market. Of course, we’d love to have the blood pressure data just for ourselves to track how we should tailor our diets.