How does the 'Fast Loading' option work?

The  Fast Loading option is one of the most important features of all our apps. By using this option, you can decide when the app loads when the page is accessed.

You can find it within the  Advanced preferences section:

If your website is heavily  customized  and if you don't want to increase your initial page loading time, then this feature helps you achieve this easily. 

Unless your store is heavily  customized,  we always suggest keeping the fast loading option enabled because our app scripts will never take much time to load. All our apps are comprised of a single script file that is minified, compressed and served from a world top CDN to ensure low latency and maximum bandwidth.

In addition, our script file is cached in the browser so it will not consume network resources after the first download.

Basically, it works in a simple way but provides effective results on the loading pattern of the page.

When Fast loading is enabled, the app script is added to your theme template and the app is loaded along with all your page resources:

When Fast loading is disabled, the app script is loaded after other resources, when page loading is completed:

Please note that 'page loading' here is a technical term which is related to what a user experiences but it's not exactly the same.