Trips can be very complex undertakings that can really benefit from software support. Often, they involve making detours to visit interesting sites in the vicinity of the main route. Different services and events can be offered at these sites. The sites may be recommended according to the traveler's needs and constraints. During the trip, the initial plan may be changed. Traveling in a group may involve synchronizing detours. Whether a trip plan is created by a professionals or by travelers themselves, it may be worthwhile sharing it with others.