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OpenCPN is a concise and robust chart plotter and navigational software program for use underway or as a planning tool. It is designed to be used at the helm station of your boat while underway, allowing you to chart a course and track your position right from your laptop. It features route navigation with ship-tracking functions, Waypoint navigation, autopilot output support, and more.
GE2KAP is a free program that enables you to create charts from GE and chart images. You can select the area from Google Earth for which you you want to create a chart, select the depth unit and the GE delay. The program is also capable of overlaying OPENCPN charts and chart images.