With Magento Facebook like discount, you can ask your customers to like your business Facebook page if they want to get the discount on products. This extension enables Facebook like banner on cart page and customers can like the page after signing in the account. 

Facebook like discount extension also enables you to create the Facebook app which verifies the user accounts and it gives discounts to customers on the checkout page. This extension helps you to grow your business on Facebook as well and you can get Facebook like discount extension for Magento with lifetime free support. 

Download Link: https://www.fmeaddons.com/magento/facebook-like-discount-extension.html