[quotemsg=11854051,0,125865][quotemsg=11853892,0,368500]I would not think so, since sound waves would interfere with the ones coming from the heartbeat. I would guess there is an app that pauses the music while getting the 'pulse'.[/quotemsg]
Since the point of the thing most likely is to provide effortless and non-intrusive measurements by reusing a transducer most people already wear anyway, cutting the sound and requiring user intervention would render this thing pointless - people will most likely far prefer uninterrupted music apart from possible rate monitoring warnings to tell you your heart rate either dropped below your workout's minimum level or exceeded the maximum.
With echo cancellation, it should be possible to detect the pulse even with music playing but that would require an ADC with high enough resolution to pick up the back-EMF from the headphones from under the sound signal.
Monitoring heartrate with a microphone attached to your body is nothing new so if they have to stop music to make measurements, that would make it pretty much un-news.[/quotemsg]
What you said is mostly true but unfortunately, I think they haven't gotten clever enough to do this without cutting the sound. That doesn't mean it's "un-news". The point is to make detecting heart rate more convenient but I think the research is still far away from being completely invisible and in the background.