There are people who buy boats but there are also people who build them, why not build your own electronics too? OpenPlotter is a combination of software and hardware to be used as navigational aid on small and medium boats. It is also a complete home automation system onboard. It works on ARM computers like the Raspberry Pi and is open-source, low-cost and low-consumption. Its design is modular, so you just have to implement what your boat needs. Do it yourself.

• Chartplotter. With OpenCPN, a navigation software with useful plugins.
• Weather Forecast. Download and visualize GRIB files with zyGrib.
• NMEA 0183 Multiplexer. Multiplex and filter data inputs from any number of serial and network interfaces. Send and filter to any number of outputs.
• Signal K (beta). OpenPlotter is ready for Signal K, the new, free and open source universal marine data exchange.
• Inspector. Check the data traffic to avoid conflicts and overlaps between sources.
• WiFi Access Point. Share data (NMEA 0183, Signal K, remote desktop, Internet connection) with laptops, tablets and phones onboard. Connect to internet on port through the same device.
• Remote Desktop. Access to OpenPlotter desktop from the cockpit through your mobile devices.
• Headless. Easy start without monitor.
• SDR-AIS. Receive and decode AIS with cheap DVB-T dongles. Calibration tools Included.
• Electronic Compass and Heel. Read magnetic heading and heel angle from an IMU sensor. Tilt compensated. Calibration tools Included.
• Barograph, Thermograph and Hygrograph. From pressure, temperature and humidity sensors. Save logs and display graphs to see trends.
• Multiple temperature sensors. Get data from coolant engine, exhaust, fridge, sea...
• Special Sensors. Detect opening doors/windows, tanks level, human body motion...
• Magnetic Variation. Calculate magnetic variation for date and position.
• True Heading. Calculate true heading from magnetic variation and magnetic heading.
• True Wind. Calculate true wind from apparent wind and either speed through water (speed log) or speed over ground (GPS).
• Rate Of Turn. Calculate the rate the ship is turning.
• Remote Monitoring. Publish data on Twitter or send it by email.
• Actions System. Compare a custom value with any data flowing through your system and use it as a trigger to run multiple predefined actions.
• Custom Switches. Connect external switches and link them with actions.
• Handle External Devices. Relays, LEDs, buzzers ...
• System Time Tools. Set the system time from NMEA data and set the time zone easily.
• Startup Programs. Select some program parameters to automatically launch at start.

http://www.sailoog.com/openplotter

https://github.com/sailoog/openplotter/wiki