RT: Page Speed Booster , 650 reviews

First of all, thank you for your interest in our app.

Regarding your question,

- This application will not increase or decrease any page load speed measures such as Pingdom or GTmetrix, Page Speed Insight, or others. Your site is not technically faster, but the user experience is highly optimized. It is also important to understand that these test tools look at the first page. Our technology is triggered on the second page. Thus you won't see any improvement in their rating. However, browse your site once the application is installed, and let yourself be impressed.

- The Page Speed Booster is using a technique called "prefetch", in which we’re actually requesting and downloading the page and storing it in the cache, right before your shoppers click the link to the page. However, this is dependent on a number of conditions (such as current tabs/threads opened by browser, the internet connection, the download process), as prefetching can be ignored by the browser, to balance itself. For example, the browser might just take the texts and abandon the request of a large font file or some images on a slow network. In a certain case, Firefox browser, it will only prefetch resources when “the browser is truly idle”.

For example, while in the Home Page, the user is currently on a page where they are making a decision of a Product to click. So, 99% of the next page will be the Product Detail Page. Page Speed Booster improves the performance of this page by having the browser retrieve the contents while the user is still thinking. Once the visitor clicks on a link, the browser only needs to retrieve the content from the browser's cache.

- Refer to the below link to get more details about increasing your page speed
https://www.shopify.com/enterprise/site-performance-page-speed-ecommerce

Hope this helps :)