The worldwide introduction of third generation mobile phone networks, coupled with advanced handsets capable of hosting rich client applications, provides a new context for mass access information systems. This infrastructure provides the opportunity to move on from the client-server and intranet models of mobile computing and build more sophisticated mass-client architectures that distribute processes and data transparently between servers and mobile clients using personalisation, push technologies and location aware services. This paper discusses the technical platform for 3G and WLAN based mobile information systems and explores an example application that leverages some of the key features of this platform using Java APIs.