This paper discusses the challenge of providing effective interaction for navigating a user's browsing history in context-aware mobile services. Mobile systems are often composed of a number of services, and navigation must be understood both in terms of a single service and of movement between different services over time. The semantics of simple navigational steps such as "back" and "forward" becomes much more complex than on traditional interfaces, and there is also a need to understand the difference between navigation based on the user's actual physical context (i.e. their real location) and exploratory navigation at a different virtual site. The challenges of composition and geography both need to be effectively addressed to build a complete and usable history of a user's interaction with the system.
['Annika Hinze', 'Knut Müller', 'George Buchanan']
Service history: the challenge of the 'back button' in mobile context-aware systems