10 things you didn’t know you could do with a smartphone

 The camera of your phone can see blood pulsing under your skin.

The developers of apps like Instant Heart Rate (available for iOS, Android, and Windows) claim that they can measure your heartbeat via your smartphone’s camera. Place your finger in front of the camera and the app will monitor small changes in the color of your skin that happens due to blood pulsation. After some time, it will be able to measure your heart rate. The Cardiio app (iOS) can measure your heart rate by following changes in the color of your face.