How the heart-rate sensor in the the Samsung Galaxy S5 works

Samsung Galaxy S5 is claimed to be the first smartphone with a built-in Heart Rate Sensor which enables users to measure their heart rate directly on their phone. Users can now check their heart rate at any time of the day and manage their condition accordingly.To measure their heart rate, users just need to place their finger on the back of the phone. The heart-rate sensor on the S5 can be used before and after exercise to measure fitness activities. It's not meant for continuous tracking.

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