Amazing!
The amount of information this app provides is amazing, there is no HRV apps out there like it, especially in terms of its diversity and reliability. The Polar chest strap is recommended for cleanest data. There is also no other app that I know of so far that measures the pulse pressure wave/Mayer wave and calculates it’s phase relation to the HRV spectrum(Berry sensor is best for this). Dan and Patrick are genius! Some things that would be useful to add to the analysis are standard HRV measurements such as SDNN(especially for long recordings) and RMSSD.