You can add a preloader to your page while the page content is still loading. It can be used on both static sites and sites using dynamic data.
For example it is really useful for large data sets:
In App Structure add new component:
And select Preloader:
Customize the background color and the preloader color according to your needs:
Set the preloader size (in pixels):
And select the preloader type:
Check the Preview checkbox in order to preview how the preloader looks. Do not forget to turn it off on your live site: