Will my app work with an unpublished theme?
Add To Cart Anywhere is designed to work on all themes. You don't need any additional configuration. However, it is possible (but not likely) that the app does not work on an unpublished theme if you're using the Shopify theme preview mode, but it should work once you publish the theme.
Please note that although the app integrates with the dynamic carts of the most popular themes, this integration will only work on the current theme and not on unpublished themes.