This paper introduces a Context Aware App for the tourism. This app is based on a graphical formalism for the context representation: The Context Dimension Tree. The aim is to propose a Context Aware approach that acts as dynamic support for the tourists, equipped of a mobile device which reacts to a change of context adapting user interface, according to his/her current position and global profile. For example, the system can guide the tourist in the discovery of a town proposing him/her events mainly interesting for the user. A case study applied to a Christmas event in Salerno, an Italian town, has been analyzed considering various users (Italian tourists, foreign tourists, etc.) and an experimental campaign has been conducted, obtaining...