Instant Heart rate Monitor for Andriod

Instant Heart Rate monitor is a nice little application for andriod phone which can determine your heart rate in roughly 10 seconds to sufficient accuracy for informational use. Works on a principle that I believe few of the non medical students are aware of, that the skin changes color slightly with every heart beat and as the application text says , a principle used in pulse oximeter. Whatever the technology behind it, this works.. :)