A good marine GPS can provide much more than just accurate positioning, with a range of plotting, sonar and safety features available. The challenge comes in deciding which of these you need, which you can do without, and what they’re going to cost. We’ve been looking at all the latest devices so we can help you decide. Along with our report, we’ve made a few recommendations. Our favorite, the Garmin Echomap 93SV, is a chartplotter and fish-finder that offers not just superb GPS but also a detailed view of what’s around and under the boat.
A GPS is inherently accurate, taking its location from satellites orbiting the earth. In order for that to be useful to us though, the detail needs to be interpreted by mapping (or plotting) software. The quality of these maps, and the detail included, should be a major factor in your decision, so care is needed when checking this information. It’s important to understand what you’re getting, because extra maps can be expensive. There may also be a fee for map updates.
Handheld GPS will tell you where you are, but little more. Mounted devices usually offer plotting features to track your course — but again, these vary. The greater the complexity, the more you’ll pay.
Sonar is frequently an option (CHIRP is a highly detailed version). This tells you what’s going on around and under the boat, including fish-finding. For some, that’s a big bonus. Others may just find it an extra expense. A transducer will need to be mounted, usually on the transom.
Advanced functions include the ability to add radar, control your boat’s autopilot, and send man-overboard positioning to search-and-rescue organizations. A similar system links automatic identification of your vessel with GPS location, should you get into difficulty. WiFi allows for wireless updating of maps, though Ethernet ports may be included (cable offers considerably quicker data transfer).
Some GPS can interact with your phone or tablet so you can control music. It may also be possible to monitor engine performance.
While handheld devices are great for knowing your position, and a boon in emergencies, they do only offer small images. Most users will prefer a screen at least 5 inches across (measured diagonally). The larger the screen, the easier it is to see detail. You also have split- and multiscreen possibilities so you can look at several sets of data at once. Touchscreens can simplify operation.
Mounting options vary, and if you don’t want to leave your marine GPS on view, or you want to use it on more than one boat, a quick-detach ability is a nice option.
Not surprisingly, handheld units are the cheapest type of marine GPS, with prices starting at around $200. Screen size, and thus the amount of detail you get, is the main drawback. Models that are 5 inches to 7 inches, most popular with inshore sailors, range from $450-$700. Models that are 9 inches are around $1,000. With screen sizes up to 16 inches available, the largest marine GPS can be close to $5,000.
A. There’s a couple of things. If you have a transducer, the marine GPS can see what’s actually under the boat at any moment. A smartphone app can’t. Positional accuracy and update frequency can also be an issue with an app. Marine GPS is still more reliable and more precise.
A. Look for an IP or IPX number (an internationally recognized standard). An IPX7 device can be submerged up to 3 feet 3 inches for 30 minutes. IPX8 can go deeper, but exact specification depends on the manufacturer. If it’s not rated, you have no guarantee. Just because it floats doesn’t mean it’s waterproof.
Garmin’s Echomap 93SV Chartplotter
Our take: Extremely accurate and comprehensive device for inland U.S. waterways.
What we like: Ultra high-definition touchscreen is clear and offers tremendous detail. CHIRP sonar via included transducer. Covers 17,000 lakes with 1-inch contours. Quick-detach mount.
What we dislike: Expensive. No coastal maps included.
Where to buy: Sold at Amazon
Standard Horizon’s HX870 VHS Radio with GPS
Our take: Low-cost alternative provides communications and positional data.
What we like: Compact voice transmitter and receiver with built-in GPS. Auto-send coordinates on distress call. Floats and is submersible to IPX8 standard.
What we dislike: Not much, as long as you realize its limitations. It is not a chartplotter.
Where to buy: Sold at Amazon
Our take: Cost-effective GPS and fish-finder for day boats and sport fishing.
What we like: Clear, easy-to-use, multifunction touchscreen. Wide-ranging compatibility with mapping and radar systems. Wireless updating. CHIRP sonar capability (requires transducer).
What we dislike: Some durability issues.
Where to buy: Sold at Amazon
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Bob Beacham writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.
