City Explorer was first develop to gain a better understanding of the challenges and potentials of end-user development in the area of mobile computing. City Explorer is a framework for city exploration that combines various levels of adaptation to the user needs. It supports:

• tailoring (e.g. creation of itineraries),
• sharing of user-generated content (e.g. creating and sharing new places),
• end-user service composition through integration with UbiSys.

City Explorer is not an ordinary tourist guide. City Explorer takes into account that users wish to experience cities in different ways. Tourists, architects, historians, children have different interests. City Explorer provides support for different forms of exploration.

City Explorer is based on the Android platform and available as open source software on github.

The software requires an information database for places and itineraries. Several test databases are avalaible from our site illustrating different facets of Trondheim:

• MiniTrondheim - A subset of tourist sites in Trondheim (database initially provided with the CityExplorer App)
• MyTrondheimBuildings - A glance at 1000 years architecture in Trondheim (subset)
• MyTrondheimSculptures - Some sculptures in Trondheim.

The users may also create databases for exploration of their preferred places in any city they want, and share them on the web, regardless the size or importance of the city. City Explorer is available to anyone and free for use.