This paper focuses on the development of a mobile service as extension of travel agencies' sales channels, fundamentally driven by the notion of value co-creation. Design goals are directly linked to the understanding of travel counselling as practical value co-creation and to the concern to progress this understanding throughout the travel customer cycle. Customers as well as travel agencies benefit from a mobile service rooted in value co-creation. Mobile service applications which target a service provision which furthermore is in line with the core competency of a travel agency (advice-giving and continuously accompany the customer) are scarce. Taking this as a starting point, we propose a mobile service and system design which provides a travel customer with continuing support on the trip, suitable to complement a lively, ongoing customer-firm interaction which enables the co-creation of value, ultimately targeting increased customer retention and loyalty.