Memory-Map's founder and chief software developer is a keen sailor. In fact, Pocket Navigator was originally conceived for exploring the intricate waters of the Thousand Islands in a small sailboat. While most of our users now are land-based, we like to keep our roots in mind, and the software includes many features for use at sea.
Of course there are many navigation systems out there you can choose from, but our focus is to bring advanced computer navigation to smaller craft - say, from power or sail vessels of 30 ft, down to dinghies, kayaks, PWC, or even wind-surfers! Even on larger craft, our systems are easy to use, and you can take them with you in the dinghy, on a charter, or wherever they are needed on the vessel.
Memory-Map uses raster charts, which are the most detailed
and trustworthy electronic charts available. In the US, the charts are
free: Free NOAA marine raster navigation charts
Most other handheld chart plotters use vector charts. With a vector chart, when you zoom out, the plotter has to decide which features to draw, and which features to hide. It cannot display all features, because it would take too long to redraw the display, and the display would be too cluttered. Even if you zoom right in, there may be features on the paper chart that are not in the vector database. With many vector charts, you don't know where the survey data came from, or who digitized it: much of the vector data commercially available today was digitized by the Soviet Union during the cold war!
A Raster chart shows exactly what is on the paper chart. It is a familiar, easy to use image of the paper chart. The full portfolio of the most detailed charts, from trusted government sources, is available. You don't have to keep looking at the paper chart to see the details that the vector plotter might not have displayed.
You can browse the charts and plan your trip on your computer at home. Plot your course and measure distances.
Print paper charts as a backup or for quick reference. You choose the exact area to cover and the scale, and your waypoints and route are overlaid. Waterproof paper will ensure the chart won't fall apart.
Program your routes, waypoints and harbors of refuge into
a handheld GPS, as a backup or for reference at the helm. Even a basic
model, without charts, is effective if you can program waypoints effectively
and accurately.
An iPhone or iPad makes a great handheld chart plotter.
Before using your iPhone on the water, I strongly recommend a waterproof case. The ones made by Aquapac work well, but they don't give much physical protection. Another good solution is the Magellen ToughCase, which is a waterproof hard case with and extra battery and a more sensitive GPS receiver.
When you are using it as a handheld, without external power, you need to watch the battery life carefully. About 5 hours continuous use is typical. If you keep the iPhone switched off when you are not using it, you can stretch a single charge out to 24 hours. A simple GPS such as a Garmin Foretrex 201 can be used as a quick reference when you don't need to look at the chart.
You can view your track-log on the Pocket PC, or upload it to your PC. See where you went, your speed at each point and what time you were there. You can view a graph of your speed profile, and compare your track to others.
You can also place Hot-spots on the map, linked to your photos, videos, text notes or voice recordings, and share it as a digital memoir of your trip. Or print a full-size relief-shaded chart, with your track overlaid, and hang it in your home or office!