How do I add custom fields to checkout?

We would like to ask customers how they heard about us as part of the order process so we can focus advertising on advertisements that work.

We would like to add a question like "How did you hear about us?" and a drop down list which had three or four options, such as, Google, Facebook, Word of Mouth, Youtube. The customer would need to select one to continue the checkout procedure.

We know we can do this by adding options to products, but having to answer the question once for every product in the cart would be a nuisance to the customer, so the best option is to ask it once in the checkout process.

How do we do this?

Hello Clifton,

EShop has the Custom Fields feature to add more fields to the checkout. You can read more about how to use it in the documentation at eshopdocs.joomservices.com/sales/fields

Hope that this is useful.
Sincerely, Giang