The mobile applications have become one of the important applications in human life, and it was widely used during the last ten years. Mobile devices can be used to do various tasks, such as browsing the internet, sending or receiving emails, and performing other tasks. Bluetooth technology is considered as one of the important specifications that were added to mobile phones during the current century where the user can use it for data and image transmission and others. One of the important applications of Bluetooth, which appeared in the last years, is the conversation via Bluetooth where users can hold short conversations using this technique. One of the most important benefits of Bluetooth technology is that it's free to send and receive messages. While the disadvantages of this application is that it is short-term, since users must be within the scope of the Bluetooth service which is (7 - 9 meters) to be able to send messages and use it.
In this paper, we will design and implement a private conversation via Bluetooth software which has the ability to work within biggest scopeby taking advantage of the properties of the (Scatternet). Each user of the application can be a crossroads for the other users. In other words, if there is, for example, users (a) and (b) 7 meters away from each other, and a third user (c) appeared within 12 meters of the first user (a). In this case, the third user (c) can be connected to the first user through the user (b). In other words, the second user (b) would be an intermediary between the first user (a) and the third user (c). So, we have been solved the distance limit problem for using the Bluetooth application. In addition, the users are now able to chat as a group (not just peer-to-peer) in a private room with a wide range using the piconet and scatternet characteristics. Netbeans 5.5, Java 2 Micro Edition (J2ME), Bluetooth API (JSR-82), Nokia Pc Suites are the tools and technologies that have been used through building this application.