Peter Gamma from www.petergamma.org repeatetely critizised Rob ter Horst for his accuracy tests about smartwatches on YouTube: https://petergamma.org/category/optical-heart-rate-sensor After Peter Gamma from www.petergamma.org has written a review about «Accuracy Studies of Consumer Grade Heart Rate Monitors: Methods, Testing Protocols, Reference Devices»: He does not know if there ever will be a second scientist next to …