MotionX GPS HD
This low-cost app has a lot of power, including the ability to directly download NOAA marine charts at no cost. It works well and has a nice UI.
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Ship Finder
This shows the AIS data from ships in any part of the world, allowing you to see large vessels in your vicinity. Functionality similar to an $800 AIS receiver.
Boating Cafe • Log Book
Nice logbook application. Track trips, fuel usage, maintenance, etc.
Weather Alert USA
Easy access to NOAA coastal forecasts and ocean weather alerts. View the full text of the alerts plus a colored wave height map and weather RADAR view.
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Google Earth
Of course, Google Earth can be useful for viewing what a harbor entrance looks like before you arrive, or even to find a marina layout before you reserve a slip so you can get one that’s convenient.
WeatherBug for iPad
An excellent weather app with easy access to cameras that show actual weather conditions. Great for planning and for reviewing the current conditions and what to expect in the immediate future as you travel.
iNmea
This app lets you view NMEA 0183 (serial) data from your instruments on your iPhone and iPad. Requires a device that connects to the NMEA 0183 source and sends the data by Wi-Fi.
Boating USA HD
Navionics did a fantastic job with their iPhone/iPad apps. It not only includes the well-known Navionics chart data, but also integrates Facebook posting, sending routes and waypoints, and more. It’s a fun way to plan trips without having to sit in front of the on-board plotter or a computer. There are separate apps for different parts of the world. The latest version covers the entire country–coasts and lakes–in a single app.
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