The idea is to bring vending machines back to their old glory: Instead of paying with cash or credit, the user can scan a QR-code with his mobile device using the vending machine app. The user does not only pay using the app, but at the same time the vending machine transmits inventory information to the mobile device, which forwards the data to the backend using its mobile internet capabilities. Like this, the mobile device is used as an intelligent gateway for the payment and inventory data, using crowd sourcing to avoid the need for each vending machine having internet access. This provides the possibility for real time tracking of vending machine inventory, optimal monitoring, always fresh on-time delivery to vending machines, dynamic pricing and many other.