Note: "Parallax" is both the name of an Out of the Sandbox Shopify theme and a generic name for a scrolling effect that is popular in web design (see this Wikipedia article for details).
If you enable the parallax scrolling effect in your Shopify theme, you will notice the effect does not work on most tablets and mobile devices.
Because this effect requires advanced code, it can cause significant performance issues on mobile and tablet devices, including "choppy" movement or even crashing the user's browser app.
The scrolling affect can also have a negative effect on user experience on mobile devices.
Out of the Sandbox automatically disables this feature on most of these devices and it cannot be enabled without custom code.
While it is possible to enable this effect on mobile devices using custom code, we typically do not recommend this because you may find that it causes your site to "crash" user's browser apps or affect user conversions.