Measurements taken without the app open on an iHealth account (called Offline measurements) are saved in the scale's memory.
All of these Offline measurements are automatically synchronized as soon as one of the user of the scale establishes a connection between the scale and the iHealth MyVitals app. This will happen, for example, as soon as one of the users makes an Online measurement (a measurement made with the iHealth MyVitals app open on his account).
Each user of the scale can then retrieve his or her Offline measurements from the Filter data menu in the app.
To do this, go to MENU > Weight > Filter data.
A page appears with all the unsynchronised measurements.
Click on the upload arrow to the right of the measurements that you want to synchronize with your account.
By clicking Edit (on an iPhone/iPad) or by pressing and holding (on an Android smartphone), the app automatically selects all the measurements corresponding to your weight (within +/-3Kg) based on the last weight measurement showing in your list of measurements. Press Upload to upload all the measurements selected to your account.
*credit to Sylvain of iHealth Labs EU