Okay, so you have took a photo of the baby, now what? Well that's pretty easy.
Since babies move a lot, the Skully Care app has a Burst-function. This way the app takes a series of 5 photos in a short duration of time. The only thing you have to do after taking a photo in the app is:
Select a photo from the 5 images below
Zoom in to check if the photo contains both ears and only the tip of the nose
Select the correct photo by clicking the button on the lower right of the image
Click on 'Yes, choose baby'
Select an baby you have measured before or add a new one