If you are a power boater on a trawler or cabin cruiser, you'll appreciate the fuel calculators offered by BoatCruiser, Nobeltec VNS, MaxSea and Nobeltec Admiral. For all boaters, a transit calculator is handy, letting you easily compute the time to an anchorage, port or restricted bridge. In general, applications with a fuel calculator also include some transit calculator. The Capn only includes a transit calculator, but it was a very nice implementation. For hobbyists or transoceanic passagemakers, The Capn, Nobeltec VNS and Admiral, and MaxSea also include celestial calculators and/or Nautical Almanacs.

Route planners are more complicated than calculators. They integrate information about your vessel and prevailing sea conditions such as wind and current to calculate an optimal route. Again, although planning features are incredibly impressive, consider whether your boating habits require optimized route planning. Passagemakers and offshore racers are most likely to use these advanced features.

Coastal Explorer, Chart Navigator Pro, both Nobeltec packages and MaxSea include auto route planners. Software-On-Board, Fugawi Marine ENC, Nobeltec and MaxSea had excellent Great Circle Route tools. For East Coast sailors who make long passages – such as to Europe, Bermuda or the Caribbean – several applications include optimization routing for sailboats, or offer it as an option. MaxSea's Sailing Performance Module and Weather Routing Module are the benchmark.

WEATHER DATA

One of the most impressive aspects of e-charting is the data available for download. Most notable in this category is support for GRIB weather data, which is available free from the government and provides detailed weather information and predictions, ranging from wave height to sea temperature. Many software applications justifiably tout their GRIB weather features.

Whether or not GRIB weather files are the best source for you depends on whether you are an inland, coastal or offshore cruiser. GRIB weather is notoriously inaccurate for near-coast predictions. For inland or coastal weather, NOAA VHF weather broadcasts are much more appropriate. You can also obtain accurate coastal marine weather information on the Internet. On the other hand, if you're sailing to Portugal, GRIB weather is an invaluable resource. It provides detailed weather information around the world. The best e-charting applications let you simply click on a location anywhere on your chart, opening a window that initiates the download of that area's weather data and predictions.

E-charting applications typically retrieve GRIB weather in one of two ways: through a SailDocs email request or through a dedicated server. Using SailDocs requires an email connection and a brief delay while the weather is emailed to you. But you are not dependent upon a private vendor's server. Software-On-Board, MacENC, Fugawi Marine ENC and Nobeltec VNS obtain weather via email. Unfortunately, you must then load it into your application manually to view it. The best GRIB weather implementation was offered by Coastal Explorer, Chart Navigator Pro and MaxSea, which maintain their own weather servers and have excellent integrated and automated weather tools.

Finally, for the offshore sport or commercial fisherman, two packages, Nobeltec and MaxSea, provide support for custom bathymetric recording. This feature, which requires optional add-on software modules and hardware, allows you to record sea bottom topography to create your own bathymetric charts. MaxSea even blends your data with its standard bathymetric cartography and can display the seafloor in stunning 3D rotating images – the ultimate in "advanced feature" e-charting eye candy.

TOMORROW: Networking, instrument support and data exchange.