Developed by Peterjohn Chisholm, Master-Nav is an educational and reference application designed to simplify the study and retention of COLREGS (International Regulations for Preventing Collisions at Sea). With over 900 questions and interactive visuals, Master-Nav offers an engaging and intuitive learning experience.

The application is divided into two sections: Learning and Practice. In the Learning Section, users can grasp the rules of COLREGS step by step, while the Practice Section allows them to reinforce their knowledge and improve their performance. Master-Nav currently covers Part A General, Part B Steering and Sailing - Section 1, Part C – Lights and Shapes, and Part D – Sound and Light Signals.

One of the standout features of Master-Nav is the app-wide Rule button, which provides quick access to the relevant COLREG rule for the question being studied. This eliminates the need to search through the rule book, saving valuable study time. Additionally, the app offers explanations in simple and understandable language to enhance comprehension of complex rules with technical terminology.

Whether you're a cadet starting your maritime career or an experienced mariner looking to refresh your understanding of COLREGS, Master-Nav is an ideal learning tool. With its comprehensive content, interactive visuals, and repeated practice opportunities, this application will help you navigate COLREGS effectively and effortlessly.