In this paper we present a web services-based platform that facilitates and speeds up the development and deployment of context-aware, integrated mobile speech and data applications. The platform is capable of handling different types of context and offers sophisticated personalization mechanisms. To illustrate the usefulness of the platform and to validate the claim that cross-platform application development, in particular mobile, context-aware applications, is easier and faster with web services technologies, we present a demonstration application. It serves tourists with interesting information and services in their specific context, and contributes to the achievement of their current goals. Finally, we present a number of problems that we experienced in the implementation process as well as the feedback that we received from real users who tested our application.