A cross-platform ship-borne GUI navigation application made up by a core program, a large set of plugins and freely available charts. The application is configurable with user icon. The core supports:
Plugin support includes wheather, tactical, annotations and tidal data. Pilot charts can be downloaded from project website at opencpn.org. Other useful add-ons may be found inside the "Download" link at at the same site.
Very nice software that installs on any OS. You will get a "Failed to inspect the lock file" error when first running it, but then all is good. Lots of functionality with this software. I highly recommend it for sailors. And surprisingly it appears to be up to date.