Sell Ecommerce Supply Chain products using the Walmart Marketplace Integration Shopify App. What is Walmart Marketplace Integration? It is a sales channel app which enables Shopify users to offer their products on Walmart.com – one of the largest online marketplace of U.S. Using this app, you can easily manage inventory, orders and shipment for Walmart Specific from your Shopify store itself. No more juggling between multiple accounts. Since online selling involves several functions which if operated manually can be intimidating, this app offers solution to all such pain points.