Hey no worries and thanks. It was a break-through for this project to find the H10 gives accelerometer data as well as heart rate, so that it would be possible to estimate breathing rate, which I haven't seen other apps do
Yes it's common to estimate breathing rate based on the oscillations in the heart rate pattern. But estimating it from the chest expansion is a more direct method
I never knew the H10 used an accelerometer, I wonder if they use it to help remove false reads during intense movements like those found in running.