The aim of this thesis is to describe the development process of an object-oriented, cross-platform control software for the Lightware Ltd. The Lightware Ltd. is leading manufacturer of DVI-, HDMI- and DP matrix switchers and accessories for the professional AV market. Although, the project focused on developing a built-in control application for the company’s new, cutting-edge modular, hybrid router, the software should function as an standalone control application, that seamlessly supports all of the company’s devices.The application was developed in the Java programming language, applying agile software development and project management processes and frameworks. At the first part of the document these techniques are discussed in detail. Then, I demonstrate the revealed drawbacks of the current control software and discuss the critical issues that must have been addressed and fixed during the development process. In the main part of the thesis, the design decisions and solutions are described in detail that were implemented to solve all of the revealed issues and specified requirements. The application must have a modern, neat and user-friendly graphical user interface, that is perfectly suitable for touch-screens as well. The document demonstrate the design and implementation of such a graphical user interface in cooperation with a designer. At the last chapter, I provide an overview of the outcome of the whole development process and summarize the topics necessary to carry out in the future.