The Top Rated Nautical GPS Units

Garmin GPSMAP 78sc

Garmin GPSMAP 78sc ($487)


  • Great display and user interface
  • Floats on water
  • Portable


  • Small screen not the best for permanent installations

Top Review Sources:

  • GPS Tracklog: “Highly recommended; probably the best marine handheld series currently made by Garmin”
  • Marine Electronics Reviews: “One of the most sophisticated marine handheld GPS units on the market today”
  • Amazon: 4.5/5.0 (5+ reviews)

The Garmin GPSMAP 78sc is a handheld GPS built for use in boating and watersports. The 78sc measures 6.0” H x 2.6” W x 1.2” D and weighs less than eight ounces with two AA batteries installed. The display itself measures 2.6” diagonally and has a resolution of 160 x 240. It is possible to hold and operate this unit with one hand—rubber sides enhance grip security. Above the screen, you’ll find eight buttons plus a directional pad, all of which control functions via a responsive and well-organized on-screen menu system. The 65K color TFT display is sharp and detailed, exhibiting no problems with washout in the sunlight. The 1.7 GB internal memory of the 78sc is preloaded with coastal charts, and the microSD slot enables you to add more maps or custom data via an external card. The microSD slot, mini USB port, serial port, and external antenna jack are all protected by a rubber cover on the back of the device. When the cover is in place, the 78sc is waterproof (and floats). If you’d like to permanently mount your 78sc, there is an optional mount and power cord available. Running on batteries, the 78sc will operate for approximately 20 hours. The 78sc is also equipped with an electronic compass and barometric altimeter. This unit comes with a one-year warranty.

The Garmin GPSMAP 78sc ($487) is for sale on Amazon. Also available is the GPSMAP 78 ($297), which is not preloaded with maps and does not have an electronic compass and barometric altimeter, and the GPSMAP 78s ($386), which also lacks the maps but has an electronic compass and barometric altimeter.

Humminbird 788ci HD Combo

Humminbird 788ci HD Combo ($606)


  • High-resolution screen
  • Very accurate GPS
  • Excellent sonar


  • Some image details are very small

Top Review Sources:

  • Cabela’s: 4.5/5.0 (10+ reviews)
  • Bass Pro Shops: 4.4/5.0 (10+ reviews)
  • Marine Electronics Reviews: “A desirable chartplotter fishfinder combo for any boater looking to upgrade their marine electronics gear”

The Humminbird 788ci HD Combo unites GPS capability with state-of-the-art sonar in a highly-regarded navigation/fishfinding device. The 788ci HD Combo has a 640 x 640, 256-color TFT screen that measures five inches diagonally. Its high resolution permits a high level of detail, though very small details can be hard to read. Viewing angles are wide, reflectivity and glare are low, and the display remains legible in direct sunlight. The unit itself has dimensions of 6.9” W x 7.5” H x 4.5” D and can be mounted either in-dash or on its included quick-disconnect stand. Its internal GPS receives praise for its impressive accuracy and tight integration with its sonar functions. Its sounding capability is similarly impressive, with 500 watts of power, multimode results display, and dual beams. The supplied transducer can be transom-mounted or mounted inside the hull. You can supplement the 788ci HD Combo’s internal memory via its two external memory card slots. This unit carries a one-year warranty.

Purchase the Humminbird 788ci HD Combo ($606) on Amazon. You’ll also find the 788ci HD DI Combo ($740), which has down imaging capability.

Lowrance HDS-7

Lowrance HDS-7 ($999)


  • Large, sharp screen
  • Very precise GPS
  • Easy-to-navigate interface


  • Included maps may not meet all needs

Top Review Sources:

  • Marine Electronics Reviews: “Excellent for daylight viewability”
  • Bass Pro Shops: 3.8/5.0 (15+ reviews)
  • Cabela’s: 4.0/5.0 (2 reviews)

The Lowrance HDS-7 is a chartplotter/fishfinder combo unit with a 6.4-inch, 480 x 640 display. Images are sharp and bright even in sunny conditions, and viewing angles are excellent. On-screen functions are controlled by means of the HDS-7’s eight pushbuttons and arrow pad. Processing is speedy and the response time of menus is above average. As with the other nautical GPS units reviewed here, the HDS-7 can save thousands of waypoints and hundreds of routes. Memory capacity is expandable via the external SD card slot. The HDS-7’s 16-channel internal GPS antenna is a strong performer, locking on to signals quickly and exhibiting outstanding accuracy. The HDS-7 will also accept an external GPS antenna if you have a closed cabin. There are a variety of mapping cards available to supplement the included Expanded U.S. or Insight USA internal maps. The fishfinder works well with the included transom-mount, skimmer transducer and is able to sound 5,000 feet. The HDS-7 measures 8.8” W x 6.4” H x 3.5” D, comes with mounting hardware, and carries a two-year warranty.

The Lowrance HDS-7 with Expanded U.S. BaseMap and transducer ($999) is for sale on Amazon. You can also purchase the HDS-7 without the transducer ($949).

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