Carrefour is the largest retailer in France. It launched a mobile marketing campaign featuring a virtual store displayed in subway stations that allows customers to scan QR codes of products and have them delivered or pick them up at a store. The multi-channel campaign utilized various advertising methods including TV, print, digital, and partnerships with the transit authority. Effectiveness would be measured through surveys, app downloads and usage, and impact on overall sales. Risks included connectivity issues and concerns over mobile payment security. Recommendations included improving integration across Carrefour apps and addressing trust in mobile payments.