The App I Loved Stopped Growing. So I Built a New One.
Foursquare was great until they split it into two apps. Most people I knew never made the jump to Swarm, and over time the community thinned out. Lately Swarm feels like a product in maintenance mode: no real new features, no momentum, just coasting.
Over 6,700 check-ins spanning 15 years of travel, dining, and daily life, all sitting in a data export ZIP file. No app on the market preserves the full Swarm experience: the gamification (stickers, mayors, streaks), the interactive maps, the searchable history, the social features. Everything available is either a stripped-down check-in tool or a location-sharing app that misses the point entirely.
Building a proper replacement traditionally would require a backend team, a React frontend team, a mobile team, a designer, and months of coordination. The scope is massive: REST API with authentication, dual-database architecture, interactive maps, a gamification engine, social features, third-party integrations (Spotify, weather, Foursquare Places), push notifications, home screen widgets, and an admin dashboard. The traditional estimate: 4-6 months and $400K or more.
One Architect, AI Tools, Five Days
MDPSync’s vibe-coding methodology: a senior architect making every design decision, with AI handling execution at 10x velocity.
Day 1: Full web application and entire backend API launched. History feed, venue pages, interactive world heatmap, stats dashboard, gamification system with stickers and achievements, lists, trips, Spotify integration, and weather backfill for all 6,700+ imported check-ins.
Day 2: Native mobile app shipped with check-in flow, MapLibre maps, stats, and push notifications. Landing page redesign with floating screenshots.
Days 3-4: Social features (comments, leaderboard, coincidence detector), 49-sticker overhaul with rarity tiers, Foursquare Places API migration, data import/export, iOS WidgetKit and Android home screen widgets.
Day 5: Venue notes and custom tags, achievement nudges, countries collection, revisit queue, trip enrichment with photos and first-visit tracking.
A Complete Check-In Platform
Check-In System
Search nearby venues, check in with notes, photos, and tags. Auto-detect trips when traveling 100+ km from home. Full Foursquare Swarm data import.
Interactive World Heatmap
MapLibre-powered heatmap with year slider to watch your travel history unfold. Country collection tracking and trip route visualization.
Gamification Engine
49 stickers across rarity tiers (Common to Legendary), 32 achievements with XP progression, mayor system, streaks, and competitive leaderboards.
History Feed
Searchable check-in history with filters by date, city, country, category, and tags. Full Foursquare/Swarm import of 6,700+ check-ins with venue details.
Native Mobile App
React Native + Expo SDK 54 with 23 screens, nearby venue picker, MapLibre maps, push notifications, and iOS/Android home screen widgets.
Spotify Integration
Automatically captures what song was playing at each check-in time via Spotify API OAuth connection. A soundtrack for every place you’ve been.
Weather Backfill
Historical weather data retroactively applied to every check-in, including all 6,700+ imported ones. Temperature, conditions, and icons on every card.
Social Features
Follow friends, comment on check-ins, coincidence detector (same venue, same day), feed broadcasts for unlocks, and shared venue lists.
Stats & Analytics
Personal stats dashboard with totals, streaks, XP progression, venue frequency, city breakdowns, and “on this day” memories from previous years.
Lists & Collections
Bucket list, revisit queue (places not visited in 90+ days), custom venue lists, countries collection with progress tracking and first-visit dates.
Admin Dashboard
Analytics, user management, cron job monitoring, venue moderation, system health checks, and audit logging for the entire platform.
Theme & Privacy
Full light/dark theme support across web and mobile, granular privacy controls, profile visibility toggles, and complete data export at any time.
See It in Action
Your Check-In History, Fully Searchable
Every check-in you have ever made, imported from Foursquare Swarm and enriched with weather data, Spotify context, and venue details. Filter by year, city, country, category, or custom tags. Each card shows the venue, timestamp, photos, sticker earned, distance from home, and what song was playing. 15 years of location history, instantly accessible.
Your World on a Map
An interactive MapLibre heatmap that visualizes every place you have been. Drag the year slider to watch your travel history unfold over time. Clustered venue pins with zoom detail, country collection tracking with first-visit dates, and auto-detected trip routes when you travel 100+ km from home. The map tells the story of where you have been and how your world has expanded.
49 Stickers, 32 Achievements, Infinite Motivation
A full gamification system built from scratch. 49 stickers across five rarity tiers (Common, Uncommon, Rare, Epic, Legendary) are automatically assigned based on venue category, time of day, and visit frequency. 32 achievements with XP progression unlock as you explore. Compete for mayor crowns at your favorite spots, maintain check-in streaks, and climb the leaderboard. Post-check-in nudges celebrate firsts and alert you when achievements are within reach.
Stats That Tell Your Story
A bento-grid stats dashboard with totals for check-ins, unique venues, cities, states, countries, photos, and mayorships. Track your streaks, view venue frequency charts, and relive past years with the year-in-review recap. The “on this day” feature surfaces memories from previous years, and the leaderboard adds friendly competition with week, month, and all-time tabs.
Check In From Anywhere
A native React Native + Expo mobile app with 23 screens, MapLibre maps, nearby venue search, push notifications, and home screen widgets for quick check-ins. Everything syncs instantly with the web app.
Feed
Map
Stats
Check In
Technology Stack
Backend & API
Web Application
Mobile Application
Self-Hosted on Raspberry Pi
The entire platform runs on a Raspberry Pi server with a Synology NAS handling MySQL 9.6, Cloudflare for DNS and security, and Fastly CDN for static assets. 20 background cron jobs handle weather backfill, Spotify enrichment, streak calculations, achievement evaluation, trip detection, push notifications, and sticker rule processing. Apache with PHP-FPM, OPcache tuning, and query optimization keep response times fast on modest hardware.
The Vibe-Coding Advantage
A complete check-in platform (React web app, native mobile app, PHP API, gamification engine, social features, and admin tools) delivered in a fraction of the time and cost of traditional development. No compromises on quality, security, or features.
5 Days, Not 5 Months
Ship a complete check-in platform with web app, mobile app, gamification, and social features in under a week. AI handles the execution while the architect focuses on design decisions that matter.
Production Quality
Not a prototype. 67 real API endpoints, Firebase authentication, push notifications, native home screen widgets, data import/export, and a full admin dashboard. Every pattern reviewed by a senior architect.
Full Stack, One Architect
Backend API, React web frontend, React Native mobile app, background jobs, third-party integrations, infrastructure setup: all designed and shipped by one person with AI assistance.
What This Would Cost the Traditional Way
Building Haunts.io through a traditional agency or staffing model would require assembling a full cross-functional team: a backend engineer, a React frontend developer, a React Native mobile developer, a DevOps engineer, a UI/UX designer, a QA tester, and a project manager to coordinate it all.
The scope includes a REST API with 67 endpoints, a React 19 web app with 28 pages, a React Native mobile app with 23 screens, 20 background jobs, a gamification system (49 stickers, 32 achievements), social features, and third-party integrations (Spotify, Foursquare, weather, Firebase, MapLibre). At market rates, that’s 7 specialists at $150–$250/hour each over 4–6 months: $400,000 to $800,000.
Vibe-coding delivered the same result: one architect, one sprint, a fraction of the cost.
Ready to Build Something Extraordinary?
Let MDPSync bring your vision to life with vibe-coding. From concept to production in record time.