HatchMatch
AI fly fishing app · 2025–present · Live on the App Store
I drove two hours to the river with all the right gear and got skunked. I thought I was short on flies. A local packing up in the parking lot showed me I was short on knowing which one to tie on, and why. Then, offhand: “You know what would be cool? If there was an app for that.”
HatchMatch is that app.
In the app
Home
Before a trip, most anglers piece the day together from a weather app, a USGS gauge, a fly shop’s guide report and a few forum threads. The river card does that legwork for any river in the lower 48: live flow, a wading call from today’s water level, the forecast, the latest guide report, and the flies to bring, ready to buy ahead. Guide reports go stale because shops can’t rewrite them daily, so the next step is letting shops keep their own report fresh.
Tap the river card for live conditions
Identify
The technology already existed. What was missing was a product built for where the problem happens: in a river, one hand on the rod, in bad light, with three seconds of patience. So the model doesn’t look up a name. It reasons about what it sees, and says how sure it is.
Match
Naming the fly is only half the job. The angler wants to know what to do next. Every ID shows the features the model saw, so you can check its work, then turns into a rig you can fish right now. If it’s wrong, you rename it. The AI is a starting point, not an authority.
Flybox
Every scan is saved. Over a season the Flybox becomes a record of what you carry, what you found on the water, and what worked.
How I built it
On the water, the angler wants one answer before the hatch is over: which fly to tie on.
The model reasons about the photo and says how sure it is. It doesn’t get the last word. When it can’t tell, the screen says so and asks for another photo. The angler can rename any fly, or retake.
I write the spec, test on my own phone, and decide what ships. Claude Code does most of the implementation.
The first version asked the model to name the fly and recommend patterns in one pass. Every recommended fly came back with the same size and the same tip. So I split the job: the model names what it sees, and a catalog of real patterns supplies the facts. I also cut notes where the model rated the photo instead of the fly.
The real thing
About 200 people have used it. A few pay. Getting it in front of more anglers is still the open problem.