Wireless network technologies, e.g. Bluetooth, enable the direct data exchange between mobile terminals. Thus, a new form of application integration becomes possible, which occurs ad hoc, contrary to the presently dominating approaches, e.g. such as EDI, which uses centralized interfaces. Possible applications of this "ad hoc application integration" are the fully digitized sales and delivery process of goods, relying completely on the wireless exchange of digital vouchers. This article presents the technical aspects of ad hoc application integration, a sample scenario describing its rationale and a prototype implementation of the sample scenario.