I couldn’t see them, but I was pretty sure the barracuda were still swimming under the dock. Earlier, they’d shimmered as they darted around in the blue glow of the underwater lights. But the lights had been switched off and I couldn’t figure out how to turn them back on. The lack of light, however, provided the perfect time to test the new FishHunter gizmo that I’d brought for the trip to the British Virgin Islands.

Last fall, Lowrance released this new concept; a castable, Wi-Fi-enabled fish finder that pairs to your smartphone. The FishHunter 3D looks like a softball-size bobber. It sports five transducers, tri-frequency, a 70-degree cone, and the ability to cast it as far as 160 feet. It even allows for towing behind a boat, proving a perfect choice for your dinghy, SUP, or kayak. It can also be used for bathymetric mapping, directional casting, and 3D structure mapping. All this is contained in a small package, allowing for powerful knowledge of your favorite fishing holes that you wouldn’t normally have with your onboard fish finder.

I slipped the FishHunter off the swim platform, letting it float between the catamaran’s twin hulls and the main dock. The device turns on automatically when wet (that, alone, was pretty amazing). I then connected my phone to the FishHunter’s Wi-Fi network and launched the free app. In “Directional Casting Mode” you are able to see the depth that each of the five transducers is measuring, and when one of the sensors detects something between it and the bottom, it lights up with a red LED. Clicking the red transducer enters you into either Raw or Fish View, and both give a more traditional fish finding view where you can identify the transducers’ reflection from the fish. After orienting myself to the screen and the transducer, one of the transducers lit up so I clicked on it. It showed two fish under me.

The fact that this gadget, when paired to a phone, can create 3D maps with bottom structure blows my mind.