Some Issues and Solutions for Complex Navigation Systems: Experience from the JRGPS Project

Navigation is a kind of application widespread especially in mobile devices. We can find complex navigation systems that combine two or more types of navigation. This can lead to a complex service, which can increase the efficiency of user's movement. The user and even the path can be characterized by a large number of variables. This fact opens a problem of finding a path that will satisfy chosen variables. We tried to point out interesting issues concerning combined navigation. For some of the issues we propose possible solutions. The solutions are based either on solutions from existing products or on our own experience from the JRGPS project supporting combination of public transport and walk.