Can the app performance be audited?

All products added to the shopping cart using the 'Add to Cart' button in that app and then purchased include the Shopify cart attribute '_Added with Also Bought button'.

This attribute can be used for app auditing and will appear in your Shopify order details page so you can know exactly which purchased products were added by the app:

The initial underscore character is a Shopify convention which tells your Shopify theme and other third-party apps that it should not be displayed to your customers.