Just an idea

Crux Bouldering App

Track your bouldering climbs, all in one place

Published 5/1/2026 56

Maker's note

I’ve been bouldering 3-4 times a week for the past three years, and got so fed up with juggling physical notebooks, scattered phone notes, and generic fitness apps that didn’t understand climbing. I built Crux to fix that—one single place to log every send, track your progress over time, connect with fellow climbers, and see exactly how far you’ve grown. We’re launching today to give the bouldering community a tool made just for their sport.

About

Crux is a mobile app built exclusively for indoor boulderers, skipping generic fitness app fluff to focus solely on your climbing journey. It’s made for every type of climber: dedicated weekly regulars, casual social throwdowns, competitive youth athletes, and even gym operators looking to boost member engagement. After a Saturday morning climbing session, you open Crux to log your new V4 send, jot a note about the tricky heel hook crux, and snap a quick photo of the route. Later that evening, you check the gym’s official leaderboard to see where you rank, and share a short clip of your send in the community thread for feedback. Right now, we’re prioritizing our core audience of serious recreational climbers first, with low-risk gym partnership tools on the horizon to help climbing spaces enhance their member experience. Unlike scattered notebooks or generic fitness apps, we’re built only for bouldering—so you get exactly the targeted tools you need to track progress and connect with other climbers.

Reviews

3 reviews · including 3 from simulated personas

0/2000 · Real user review
  • Mia CarterAI persona· Serious Recreational Boulders (Weekly 3-5x)
    Graphic Designer for Outdoor Gear Brand·14d ago

    Right now I use a separate physical notebook for each of my regular Portland gyms—Planet Granite and Brooklyn Boulders PDX—so I constantly forget beta or mix up grading scales when I switch spots. I’d absolutely switch to a dedicated bouldering app if it had a free 14-day trial that syncs directly with those gyms, supports both V-scale and Font grading, and has accurate, auto-updating local leaderboards. Manual tracking eats into time I could be spending climbing or prepping for regional comps.

  • Javi MüllerAI persona· Serious Recreational Boulders (Weekly 3-5x)
    Mechanical Engineer·14d ago

    The two biggest immediate dealbreakers would be a monthly fee over €8, or no support for European Font grading. Half the gyms I climb at in Neukölln use Font instead of the V-scale most mainstream apps default to, so I couldn’t log my sends accurately if it lacked that. My current Google Sheet setup also lets me track sends across three different local gyms easily, so not having multi-gym profile support would be a major hassle too.

  • Zoe ReedAI persona· Serious Recreational Boulders (Weekly 3-5x)
    Assistant Climbing Coach·14d ago

    Oh, so many frustrating bits. Generic fitness apps don’t properly support the V-scale bouldering grading we use at local NYC gyms, and most don’t let me switch to Font scale when I climb at out-of-town spots. My old physical notebooks get lost constantly— I’ve gone through three in six months— and flipping through pages to track a specific send or check my long-term grade progress is such a hassle. Plus, there’s no easy way to share beta notes with my student climbers straight from the log.

Reviews from simulated personas were generated by LLMs during pre-launch research to surface how different customer segments might react. Real reviews are written by signed-in launchsims users.

AI panel verdict

Conditional

This product's trajectory most resembles early Cluely — a niche mobile bouldering tracking app built exclusively for indoor climbing enthusiasts, with a clear core audience of serious recreational climbers. It has viable long-term upside if the team strictly prioritizes its highest-value user segments and avoids overinvesting in casual, low-retention users. However, it faces a high risk of a rapid retention cliff or permanent shutdown if it expands too broadly without monetization safeguards, as seen in Cluely's failed mass expansion. The strongest path forward involves doubling down on core B2C users while adding low-risk B2B gym partnerships to diversify revenue.

Real-world analogues

  • Cluely0.95

    Launched as a B2C bouldering tracking app with leaderboards and community, it grew to 100k monthly active users via niche social media before seeing 65% 30-day core user retention drop as casual users flooded the platform. The key lesson is that overextending to non-core audiences will erode unit economics and alienate loyal power users.

  • TrainingPeaks0.7

    Started as a B2C competitive triathlon tracking tool, it pivoted to B2B enterprise tools for coaches and gyms after struggling with unsustainable casual user churn, and now operates as a profitable subsidiary of Wahoo Fitness. The lesson is that niche B2C fitness apps can extend viability via B2B partnerships with venue operators.

  • Path (2010 Social App)0.6

    Built as a tight-knit mobile social app for close friends, it failed to balance core user needs with mass expansion, leading to a 70% drop in daily active users within 12 months before being acquired and shut down by Facebook. The lesson is that overbroad onboarding will alienate core niche audiences.

  • Strava0.55

    Started as a cycling-specific tracking tool with leaderboards, it retained its core niche audience by preserving specialized features and expanding only to adjacent sports, growing to a $1.2B public company. The lesson is that targeted specialization can drive long-term loyalty if paired with optional premium features for power users.