A Montana company that sells digital navigation apps to hunters, off-roaders and backcountry hikers has turned to Minnesota anglers to help develop apps for both trout streams and freshwater lakes.

OnX Maps, best known for its GPS-driven hunting app, acquired Twin Cities-based TroutRoutes this year at about the same time it originated onX Fish out of the offices of a Cannon Falls software developer. The mobile apps help anglers plan fishing trips with highly detailed information about species abundance, where to fish, when to fish and how to get there.

Still in its development phase and only available in Minnesota, onX Fish is being created by geographic data master Joel Nelson with feedback from Minnesota anglers who have discovered the app by word of mouth. OnX, based in Missoula, Mont., with a workforce of 400, hopes to commercialize the app. For now, it's free.

"We have thousands of daily users and we're hearing from them," Nelson said. "Minnesota is the perfect test case."

The other app, TroutRoutes, was six years in the making and the first app of its kind when onX took it over March 20. Founder Zach Pope, who lives in Bloomington, said he sold his start-up company knowing that onX would keep him and hire his four Twin Cities employees — all avid fly anglers who were early TroutRoutes customers.

Pope graduated from Academy of Holy Angels high school in Richfield in 2006, earned a master of technology degree from the University of Minnesota and founded TroutRoutes in 2019. Terms of the takeover were not disclosed, but Pope said the purchase was rewarding for his investors, including Traction Capital of Wayzata.

He characterized the sale of his business as a dream come true and "a successful outcome for an entrepreneur."

Neither of the Minnesota-tempered fishing apps will tell users where fish are biting. "We want to avoid hot-spotting," Nelson said.

Rather, they provide an array of information for anglers to plan their trips and to aid them on the water with current stream flow readings, lake contours, traditional fishing holes, site-specific fishing regulations and personal GPS waypoints saved from the user's previous outings, among other data.

Pope said TroutRoutes has already improved under onX's ownership. Greater detail achieved by onX Maps can better instruct fly anglers on how to follow public land to lesser-used trout waters and shores. Even in remote valleys, the app provides reliable route guidance if the user downloads a map of the area while still in range of an internet signal.

TroutRoutes was the first fly angling app to map every trout stream in the U.S., Pope said. The app assigns fishing ratings to each one, from Gold or Blue Medal (elite) to Class 3 (least productive).

Now, with added tech and financial muscle supplied by onX, the app is being adapted for Apple CarPlay. Pope said there are lots of other ways TroutRoutes will improve. His goal is to add features making the app top-rated in three ways: where to go, when to go and how to fish when you get there. For now, the pricing for subscribers is straightforward: $60 a year for the whole plan. A minimalist version of the app can be downloaded for free.

"There's lots of ways we can get there faster because onX has way more experience, way more capital," Pope said.

For now, TroutRoutes is installed on about 500,000 phones, but only a fraction of the downloads are paid subscriptions, Pope said. The largest customer bases are in Minnesota, Wisconsin, Colorado, Montana and the Northeast, particularly Pennsylvania and New York.

At onX Fish, there's no precise date for when the free trial period will expire. The company envisions a tiered subscriber base, but prices haven't been assigned. Adding other states to the app will happen next, probably starting with Wisconsin, Nelson said. Key to the development so far are surveys sent to random Minnesota users. Nelson said the responses have been thoughtful and instructive.

"Minnesota is our proving ground," he said. "We've had a ton of input from intermediate to advanced anglers. They know that there's always more to know."

Nelson was sought out by onX to launch its first fishing app. He's an avid angler who has worked at several Minnesota fishing companies, including Otter Outdoors of Maple Lake, MarCum Technologies of New Hope and St. Croix Rods. He honed his geographic information system (GIS) skills at the University of Minnesota's Department of Soil, Water and Climate.

Unlike other lake fishing apps, onX Fish doesn't incorporate waypoints generated through crowdsourcing — a method that could send too many people to areas where others have been hammering fish. Nor does the app provide the kind of fishing reports issued by lake resorts, bait shops or chambers of commerce. Rather, the maps have waypoints of historically well-known fishing holes cataloged by an established paper mapping company. Clicking on any of the waypoints pulls up a narrative of how people typically have fished it and what species have been caught.

Public data created by the fisheries division of the Minnesota Department of Natural Resources provides the backbone of information sorted and displayed by onX Fish. It's partly the same information that anglers can find on the DNR's online LakeFinder tool, which is now mobile. Similarly, the DNR provides — free of charge — an electronic outdoor recreation mapping tool called Recreation Compass as well as StreamFinder, a work in progress that doesn't cover all trout streams in Minnesota but provides fishing regulations, fly-fishing access sites, fish stocking information, fish consumption warnings and aquatic plant survey information.

Nelson said the value added by onX is sorting and interpreting DNR data. "We'll make it ultimately more searchable and usable," he said.

A case in point is a primary feature of onX Fish that categorizes the DNR's fish survey data, achieved by crews netting various species and analyzing those populations.

Using onX Fish, an angler can scan what lakes are in a certain area and call up a filter that informs the user if a certain lake contains any fish of trophy potential, which species in a given lake are in high abundance or what area lakes have good "keeper potential," all sorted by the angler's desired species.

"Toggle the Keeper Potential Filter, and instantly see a list of lakes that meet keeper criteria," the company says in one of its promotions for onX Fish.

Another feature, which is particularly useful to ice anglers, provides continuously updated satellite imagery of the lake you're on or planning to fish. Under the right conditions, the user can identify tracks or trails to fishing areas or find where there have been deep cracks or open water.

Ice anglers can also look at lakeside land to identify remote access points from public land for snowmobiles or ATVs. As with TroutRoutes, users of onX Fish can check up-to-date regulations wherever they go.

Nelson said onX Fish also has its own weather feature and can be used as a live GPS device in remote areas if the area map is downloaded before the user is out of range of a signal.

"The more time people spend with this app, the more time they want to spend in the app," Nelson said.

So far, with the app barely marketed and still in development, Nelson said there are on average several thousand daily active users.