The "related products" feature can be added from within your theme editor.
In the newest versions of our themes, this recommendation algorithm uses sales data and product descriptions to show a mix of products that are similar or often bought together.
Product recommendations become more accurate over time as new orders and product data become available.
The algorithm that identifies recommended products is based on data about products that were purchased together and products with similar descriptions. It uses this data to provide a mix of those related products as recommendations for a given product.
In cases where purchase or product description data aren't available for a given product, products from a related collection are shown.
The algorithm uses the collection in the URL from which the request to the API endpoint originated, and pulls other products from that collection.If the product doesn't have a collection URL, then the recommendation algorithm finds collections that include the product and pulls other products from those instead (excluding collections with handles “all” and “frontpage”).
Older versions of themes feature different coding where a customer must first choose a collection and then inside that collection select a product - if you go to a product first, the theme won't know which collection it is to pull related items from.
For reference, the algorithm based "Recommended products" update was added first in the following theme version:
Add "related products" by navigating to:
Online store → themes → customise
Navigate to "product pages" in the dropdown selector within the editor.
Select "product pages" which should then appear on the left-hand side settings panel.
Select "enable" under "related products".
To edit the default text "You may also like...", simply add in your own text in the "heading" field:
If you require additional functionality, with more manual control, we would recommend the app 'Cross-Sell', which should fit your requirements: