CardiacSense has a state of the art watch (the current device has successfully passed 2 clinical trials with sensitivity of 99.5% and specificity of 95%).
Meaning that we are 1 to 1 compatible as ECG (no influence of movement artifacts that as you well know are the Achilles heel of PPG).
This wristband can detect Heart Arrhythmias over the wrist (with focus on A-Fib) and measure BP continues.