Please test the sensor with you small finger like the video shows to see if the sensor part itself is working alright: 

https://www.youtube.com/watch?v=zu7gvGWTuwc

Please also note that unlike an adult finger clip sensor which is solid in shape, baby sensor of cloth wrapping type has its limitations, it is easy to be changed in position loosing signal.

It will need more attention from parents regarding adjusting placement.

If not getting reports on the app ViHealth after use of the device, please check the tips below:

The device starts saving data when a period of measurement ends. ( when you unplug the sensor cable and countdown finishes.)

Then when connecting the app "ViHealth", the app will check if the device has newly recorded data. If it does, the newly recorded data will be synced to the cellphone, and you can see it on the History page.

About Connecting to cellphone: 

APP "ViHealth" can be downloaded from Google Play or App Store.

Notice: DO NOT pair it in the bluetooth settings of the cellphone.

First, make sure your cellphone's bluetooth is on,

1) Please power on the device, for BaByO2S2, please power on it by pressing the side button, so the device can be discovered by app ViHealth.

 2) Please open app ViHealth

For running the app for the first time, it directs to a page “Add your device”, will show icon of the device found near the phone.

Tap the device icon to enter.

In other cases, it either goes to the page of “Choose your device” where you need to tap the icon of your device to enter.

Or goes back to the last page where you left the app previously, the app will find the corresponding nearby device to create the bluetooth connection automatically.

 When the device is connected with app ViHealth, you can tell from the Battery status on Dashboard page.

The question mark on the bluetooth station(box) means it is asking for the pairing between the bluetooth station and the BabyO2 monitor.

Please follow the tip or video below to pair it.

1) Press both buttons of the bluetooth station to enter searching mode.

2) Power on the BabyO2 by pressing the side button of it.

3) The bluetooth station will find the BabyO2 moinitor and displays it with the last four serial number.

4) Press the volume button of the bluetooth station to complete the pairing.

You can also check the video below:

https://1drv.ms/v/s!Ah_Fwna2LoEkgVq6l0TQZxVcKaDB?e=z1bM1q