To use the RE.DOCTOR PPG Vitals Scan to check your vitals:

Download the RE.博士 app on your smartphone.
Open the app and select the “PPG Vitals Scan” feature.
Place your finger over the smartphone’s camera lens and hold it steady.
The app will use photoplethysmography (PPG) technology to measure your heart rate, blood oxygen level (SpO2), blood glucose, and respiratory rate.
The app will display your vital sign measurements on the screen.
The RE.DOCTOR PPG Vitals Scan provides a convenient way to monitor your health metrics from your smartphone.