Your Mountain.
Your Crew.
Your Best Shredd.

GPS-powered ski tracking, real-time friend finding, AI session planning, and 30+ resorts mapped in stunning 3D. Built entirely on Replit for the 2026 Buildathon.

Download on TestFlight See Features
Copper Mountain Map
Snow Report
Strava Integration
GPS Tracking

Every Run, Every Metric

Precise GPS-powered tracking that captures your entire ski or snowboard day. Auto-pause on lifts, real-time trail matching, and detailed run-by-run breakdowns.

  • Distance, vertical drop, max speed, and duration per run
  • GPS-to-trail matching with confidence scoring
  • Store-and-forward for areas with no signal
  • Automatic resort detection from 30+ mapped resorts
GPS Recording
Trail Map
Live Conditions

Real-Time Snow Reports

Check conditions before you drive. Live lift status from Liftie.info and SnoCountry, real-time weather, snowfall history, and webcam feeds -- all in one place.

  • Per-resort snow reports with base/summit depth
  • Live lift and trail status with color-coded indicators
  • Automatic nearest-resort detection with GPS
  • 30+ resorts across the US and Europe
Snow Report Copper
Resort Hub
Integrations

Strava & Garmin Sync

Connect your existing fitness accounts. Import activities with automatic duplicate detection, view unified stats, and export sessions with full GPS data.

  • One-tap Strava and Garmin account linking
  • Smart duplicate detection across providers
  • Season stats with year-over-year comparisons
  • Full session history with detailed activity cards
Strava Connected
Session History
AI-Powered

Smart Session Planning

Tell Shredd your skill level and how hard you want to go, and it plans your perfect day. Choose from 30+ resorts with search, favorites, and home resort settings.

  • AI itineraries tuned to skill level and intensity
  • Resort search with favorites and home resort
  • 40+ achievements across 7 categories
  • Shredd Points leaderboards with skill modifiers
Resort Picker
Session Planner

See It In Action

Scroll through real screenshots from the app running on iOS via Expo Go.

Copper Mountain Map

Copper Mountain

Snow Report

Snow Reports

GPS Recording

GPS Tracking

Strava Integration

Strava Sync

Session History

Session History

Resort Picker

Resort Selection

Resort Hub

Resort Hub

Resort Hub

Resort Hub

Connect Accounts

Connect Accounts

Trail Map

Trail Maps

AI Session Planner

AI Planner

Resort Details

Resort Details

Achievements

Achievements

Activity Detail

Activity Detail

30+

Resorts Mapped

40+

Achievements

3D

Terrain Visualization

100%

Free to Use

Built Different

Powered by real data sources and modern engineering -- no mocks, no shortcuts.

3D Terrain with Real Elevation

NASADEM elevation data from OpenTopography, OSM trail polylines, and Spline-powered rendering with chunked progressive loading.

GPS Trail Matching

Frechet distance algorithm matches GPS paths to known trails with confidence scoring and direction detection in real-time.

Live Lift Status

Real-time lift and trail status from Liftie.info and SnoCountry with smart caching, automatic failover, and 15-min refresh cycles.

Cross-Platform

React Native + Expo targeting iOS, Android, and web from a single TypeScript codebase. Express + PostgreSQL backend with Drizzle ORM.

Privacy-First Social

Three-layer privacy model for friend location sharing: global toggle, per-friend permissions, and time-limited shares with request/approve flow.

Store-and-Forward GPS

Offline-capable GPS caching inspired by RTRT.me architecture. Queues location data locally and batch-uploads when connectivity returns.

Built entirely on Replit

Shredd was designed, coded, and deployed using Replit Agent -- from database schema to 3D terrain rendering, all within one workspace. Submitted to the Mobile App Replit Buildathon 2026.

Download Shredd

Now available on iOS via TestFlight. Get early access and help shape the future of ski tracking.

Get Shredd on iPhone

Tap the button below to install Shredd via TestFlight on your iPhone or iPad.

Download on TestFlight

Requires iOS 16.0 or later. TestFlight will be installed automatically if needed.

Special Notes

A few things that make Shredd unique under the hood.

3D Terrain Generator

Every resort map is generated from real NASADEM elevation data via OpenTopography and trail polylines from OpenStreetMap. The terrain mesh service produces GLB files with procedural trees (GPU instanced), dynamic snow objects, and color-coded trails. Chunked progressive loading streams 500m terrain tiles at 3 LOD levels so the scene loads smoothly even on mobile.

Real Data

GPS Trail Matching Engine

As you ski, the app matches your GPS path to known resort trails in real-time using the Frechet distance algorithm. It scores each match with a confidence level and detects which direction you traveled -- distinguishing between skiing down and riding the lift up.

Algorithm

Live Lift Status with Failover

Lift and trail status comes from Liftie.info and SnoCountry APIs with smart caching (15-min fresh, 60-min stale TTL). If the primary source goes down, Shredd automatically fails over to the backup source -- no manual intervention needed.

Live API

Privacy-First Friend Location

Location sharing uses a three-layer privacy model: a global toggle, per-friend permissions, and time-limited shares with a request-and-approve flow. Friends can only see your location when you explicitly allow it, and shares auto-expire.

Privacy

Store-and-Forward GPS

Inspired by RTRT.me's Ironman tracking architecture. When you lose signal on the mountain, GPS data is cached locally and batch-uploaded when connectivity returns. You never lose a single data point from your session.

Architecture

Terrain Export for Game Engines

The terrain system exports to GLB, OBJ, and PNG heightmap formats with configurable vertical exaggeration. These exports include trail geometry, lift lines, run boundaries (computed via Graham scan), and 3D labels -- ready for import into Three.js, Spline, or any game engine.

Export

Strava API Compliance

Shredd fully complies with Strava's API terms. Imported activities are private to each user -- they are excluded from leaderboards, cannot be shared publicly or in groups, and do not contribute to Shredd Points visible to others.

Compliance