Fish finders aren’t just for bass boats anymore. Portable and castable sonar units have made underwater detection accessible to bank anglers, kayakers, and ice fishers. If you fish unfamiliar water, a fish finder pays for itself in saved time.
Types of Portable Fish Finders
Castable sonar (Deeper, iBobber): A sonar ball you cast out with your rod. Connects to your phone via Bluetooth or Wi-Fi. Shows depth, bottom structure, fish arches, and water temperature. Best for: bank fishing, kayak fishing, scouting new water.
Handheld/portable units (Lowrance, Garmin): Traditional sonar with a portable transducer you clip to a boat or drop through ice. Better resolution than castable units. Best for: kayak fishing, small boats, ice fishing.
Top Picks
Deeper PRO+ 2 ($250): The premium castable fish finder. Dual-beam sonar (wide and narrow), GPS mapping, Wi-Fi connection, 330-foot depth range, and it creates bathymetric maps of your fishing spots. Cast it out, reel it back in, and you’ve mapped the bottom.
iBobber Castable ($90): Budget-friendly castable sonar. Bluetooth connection, fish alarm, depth readings to 135 feet. Lower resolution than the Deeper but 1/3 the price. Perfect for casual anglers who want to see depth and structure.
Lowrance Hook Reveal 5 ($300): Not fully portable out of the box, but Lowrance sells a portable kit ($50) that turns it into a complete unit. CHIRP sonar with SideScan gives you the clearest underwater images in this price range. Best for kayak anglers who want boat-quality sonar.
Garmin Striker 4 ($120): Compact, rugged, and dead simple. CHIRP sonar, waypoint marking, flasher mode for ice fishing. The 3.5-inch screen is small but readable. Best all-around portable unit.
Where to Mount
- Kayak: Transducer arm mount or through-hull scupper mount
- Bank fishing: Castable sonar — no mounting needed
- Ice fishing: Flasher mode on Garmin Striker or traditional flasher unit
- Small boat: Suction cup transducer mount
Worth It?
If you fish the same familiar spots, a fish finder is optional. If you explore new water, fish from a kayak, or ice fish — it’s essential. Start with a castable unit if you’re unsure.