I think HRM is more useful than compass/barometer since HR is the only thing your phone can't do. The https://www.whoop.com/ https://www.whoop.com/, for exampl

I think HRM is more useful than compass/barometer since HR is the only thing your phone can't do. The https://www.whoop.com/ https://www.whoop.com/, for example, doesn't even have GPS. All of its value comes from its HRM. Barometer is especially niche and not something very trustworthy outside of devices made for it. To the average person, compass is only useful for showing orientation on a map.