Thank you for the graph. The peaks in your data do look easier to see than mine (but that might just be the graph scale - I'll have a proper look later) It looks like just over 60 bpm. Is that right? Did the watch report something similar?
Regards
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Something like this?