We are planning to build an app that will allow customers to use loyalty points on their checkout process (At the moment the point system is 3rd and isn't part of shopify ). Our customers will pay for the order through the loyalty points (Means no actual currency payment). The customers will connect with the loyalty partners through our application. (Using APIs available from our different loyalty partners.)
On the checkout process we will fetch the customer poinst information from the 3rd party service and display that to the user which the user will use for payment of their order. I want to know if this is possible to do in shopify or not? and if it is possible then how can I edit the checkout template and process to add such option?
I looked for some options and quick approach that came to mind was to build a custom payment page and use the Hosted Payment SDK to integrate our hosted payment page with Shopify's checkout.