First, you would need a mobile device that has a back camera with flash.

Then, place your finger on the back camera.

Remember to turn the flash on before recording.

Your video should be at least 10 seconds.

You can upload a video, or record directly from Pulsebox by clicking capture.

Now you’re all set to retrieve your heartrate from Pulsetracker.

Guide to PulseBox was originally published in pulsetracker on Medium, where people are continuing the conversation by highlighting and responding to this story.