Duty-free shopping is a large part of the airport experience for many travelers who are traveling internationally. Visitors passing through should be presented with the offer to quickly opt-in for updates from the duty-free shops via their cellphone. With a simple form, employees can collect customer information at point of service. Customers can choose to receive messages either via SMS or email. Now, when you have new deals to advertise just send out your promotions and customers will receive it on their preferred channel.