Automatic Identification Systems (AIS) currently used to detect and warn about possible maritime navigation collisions are a suitable solution for well equipped ships, but are unfortunately quite expensive and difficult to maintain for small ships and pleasure boats. The Share-Loc project purpose is to design and implement an alternative maritime navigation system for small ships and boats. The Share-Loc system is made of a navigation database server and mobile navigation clients. It is based on a client server architecture that maintains a global view of a given navigation area on the server side, and a WAP-based solution that provides location-based data on the clients side. The server is a web-based program running on an Internet connected computer. Each client is a WAP-enabled mobile phone device that accesses the WEB server data through a WAP gateway program running on the server computer. Mobile clients are connected to Internet service providers according to their choice of telephone handset and mobile telephone network. Subsequently each authorised client is able to request the appropriate UML address on the server and to start the navigation-based application.