Why is screentime and app usage reporting different numbers?
If you click the blue &quot;SHOW CATEGORIES&quot; button, you'll see the categories listed in the list at the bottom of the screen. You can see what usage is labelled as Social, Education and Creativity - the rest of your usage is shown as the grey bar.
This can include for example having the phone displaying the lock screen or the home screen. It does not count as time for any particular app, and thus do not interfere with your app limits - but it is still counted as time the phone is displaying something.