John Ballinger has developed Heart Monitor (App Store; $4.99), an App which makes use of the iPhone’s microphone capabilities to detect heart rate.
Ballinger’s demonstration of Heart Monitor:
iPhone App – Heart Monitor from John Ballinger on Vimeo.
This App is not meant to replace an actual heart rate monitor
but if used correctly (read: in a quiet environment and placed
correctly on the body), Heart Monitor can be a useful tool, especially
for athletes in training.
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