I will give you an update on the application I am developing for my handheld PC. I am going to give an overview of the problems I encountered in porting a Java application to a handheld device using Windows CE. The application is supposed to be some kind of Mobile KBS based on the Prolog system I presented earlier. Especially the KBS part presents a major problem in the development of this application and I will explain you how I tried to deal with this. You will also see a prototype of the application.