Water temperature changes with depth, creating layers of warmer and colder water from the surface to the bottom. Fish and their food sources have strong biological responses to these temperature changes, and every species has a specific temperature range where it feels and feeds best. When you know exactly where that “comfortable” water is for the fish you’re targeting, you can ignore dead water and put your lures at the depth where they are most likely to bite.

That’s exactly what Fish Hawk TD Connect™ does. This one-of-a-kind temperature and depth sensor provides a complete profile of the water column with a single drop, revealing exactly where your target species’ preferred temperatures occur. Instead of guessing or relying on surface temperature readings, TD Connect allows you to lock onto the precise temperature ranges of “right water” for each species in lakes, reservoirs, and the ocean faster and more efficiently than any other tool—so you spend less time searching and more time catching.
Just clip TD Connect to your fishing rod and line with a weight, drop it to the bottom, reel it back up, and open the free TD Connect app. There are no buttons, menus, or setup; the device automatically turns on when it hits the water and records temperature and depth as it descends. As soon as it comes back out of the water, the full temperature and depth profile is sent wirelessly and instantly to your smartphone or tablet.
On the app, you will see exactly how temperature changes with depth and choose to view the profile in 1', 5', or 10' increments. Enter your target species’ preferred temperature range in Target Temp Mode, and the app highlights the precise depths where that band of water exists, so you can immediately target the real strike zone. Every drop is automatically saved in your personal logbook with date, time, and GPS location (no cell service required), and you can add your own notes or share data with partners via text or email.

TD Connect is more than a temperature finder; it’s a powerful tool for finding the running depth of your presentations. Use it with Dipsy Divers, leadcore, downriggers, and other trolling setups to see their true running depth in your real‑world conditions and build your own dive charts for repeatable, confident spreads.
TD Connect works in fresh and saltwater and connects wirelessly to iOS and Android devices in North America. The app supports multiple TD Connect units and allows you to select between feet and meters, Fahrenheit and Celsius. An internal lithium-polymer battery provides days of use between charges, with the app displaying battery status, and wireless charging makes it easy to top off between trips.
Made in the USA for anglers who want to spend less time guessing and more time catching, Fish Hawk TD Connect™ delivers information no traditional fish finder can provide—true water temperature and depth, top to bottom, right where you fish!
*The mobile app is unavailable outside North America at this time.
Download the complete User Guide
iOS 18.0
Compatible with iPhone XS / XR and newer (any iPhone from 2018 onward.)
Android 12
Compatible with most phones manufactured from 2020 onward, plus many flagship phones from earlier years that received the Android 12 update.
This thing works as advertised, was able to successfully target kokanee salmon at 78 feet, 55 degrees, it's pricey but if you are a serious fisherman it's worth it
Amazing device. Hook it to your line and toss it overboard. Let it go to bottom. Reel it in and you have a written record of the temperature every foot to the bottom. All of the data is right there in front of you on your phone with a map of where you took the reading along with the date. I don’t know what more you could want? This device is already put fish in my box 1st time out. Once you figure out where the thermocline is, and it varies in different places on the lake, it really narrows down where you fish or look for fish. To me this is as big as live scope for a lot less money. I realize I’m talking about two completely different things now but if you fish in lakes that develop thermoclines, you want this.
I had been looking for a product that would tell me the depth my lure was at, while trolling with a variety of rigging. I also, wanted to be able to determine the water temperature column. I've been keeping a eye out, for a product like the Fish Hawk TD, for 2 or 3 years. Still learning to use it, but appears to be just what I wanted.
Works as it should so far, still new.
I like it
The only problem I have so far is in sending copies of the data to friends fishing it is only a brief summary at 20 ft increments.
(Disclosure: I am the developer of the "Get Hooked!" fishing app and am currently using this device as part of my personal research for the app.) I’ve only been using the Fish Hawk TD Connect for a short time, but it’s already proving to be a solid, compact tool for Great Lakes trolling. It provides the precise temperature-at-depth data I need to start dialing in my spreads for walleye and salmon. I’m currently integrating this data into my own app, "Get Hooked!", to help refine our predictive engine. Even with limited time on the water, the accuracy of this unit is clear, and it’s a great investment for any angler looking to get more technical. I’m looking forward to gathering more data as the season progresses.
The Fish Hawk TD Connect is a major improvement over the original Fish Hawk TD. All of the Temperature/Depth readings are stored on your phone. Just install the app on your phone. Easy Peasy
works really great definitely takes the guess work out of depth of water temp.