How to set up a free item with shipping only for social media shares?

[DressFive]

I am trying to create a discount that will allow the customer to pay shipping only and get the item for free if they like and share  the site on Instagram and Facebook.

[shareiteffect]

I'm not sure if this is something that Shopify offers.  However, there are many ways to offer a discount to your customers.  I believe my app could help you get the same results you're looking for. Let me know if I can be of assistance.  Make it a great day!