Following the measurement instructions is very important to getting precise measurements. Please make sure that you follow these instructions every time you measure:
Sit still without moving or talking
Try to keep your posture and your hand relaxed as you measure.
If you have had physical activity, wait for a while until your heartbeat is back to normal.
Cover the camera completely, and if your phone has several cameras, make sure you are using the one that is shown in the instructions.
If you have taken the measurement correctly and the result is still inaccurate, please contact us and describe the issue in as much detail as possible so that we can discover where the problem is and fix it.