4. 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.
5. You can scan and digitize old negatives with the help of your smartphone.
This is not the best way to scan and digitize negatives but if you urgently need to look through your old negatives, the negative effect of your camera can help. You can also try using some available apps like HELMUT Film Scanner (available for Android).