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Nine apps on the App Store.
Some mine, some my clients'. All still running.

I'm Minho, a React Native engineer in Seoul. For 8+ years I've shipped iOS and Android apps — for clients and for myself — and I drop into native Swift when a job needs it. I take apps from idea to App Store to revenue, build the web and backend they run on, and I don't disappear after launch.

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React Native
·
Swift
·
Expo
·
TypeScript
·
AI Integration
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Subscriptions & Billing
·
Offline-first
9Apps live on the App Store
4.8★Rating on Chingu, my newest iOS app
4 yrsLongest client app, still updated
8+Years shipping React Native

Client Work

Mobile apps I built for other people's businesses — plus the web platform I keep running for one of them. Every one is still live, and the oldest shipped in 2021 and still gets updates from me.

Shackpets screenshot

Shackpets

iOSAndroid
ClientShacknewsGamerhub Content Network2021 – present · still shipping updates

Pet battle app for Shacknews. Users compete in daily cuteness battles and win prizes.

Role

Lead React Native Engineer

What I shipped

  • Built the gamified pet battle system on Shacknews' Cortex engine
  • Implemented daily voting mechanics and leaderboards
  • Shipped and maintain both iOS and Android apps with push notifications
  • Integrated prize fulfillment and the user reward system

Key features

  • Daily pet battle tournaments
  • Community voting system
  • Prize and reward mechanics

Metrics

4.4★App Store rating
4+ yearsIn production

Tech Stack

React NativeTypeScriptCortex EnginePush Notifications
App StorePlay Store
Laundry Homes screenshot

Laundry Homes

iOSAndroid
ClientLaundry HomesKorean on-demand laundry service2020 – 2024 · 4 years in production

O2O laundry service. Customers book pickup, washing, and delivery end to end.

Role

React Native Developer

What I shipped

  • Built the customer-facing booking and order tracking app
  • Built a second admin app for factory staff to manage incoming orders
  • Integrated real-time location tracking for pickup and delivery
  • Implemented payment processing and order history

Key features

  • Real-time order tracking
  • Scheduled pickup/delivery
  • In-app payment processing

Metrics

2 (customer + ops)Apps shipped
4 yearsIn production

Tech Stack

React NativeTypeScriptFirebaseGoogle Maps
App StorePlay Store
Restart screenshot

Restart

Web
ClientRestartWalmart-backed gaming media companyOngoing · monthly retainer

Ad-free gaming news, previews, features, and reviews.

Role

Fullstack Developer

What I shipped

  • Build and maintain the editorial platform for a Walmart-backed gaming publication
  • Developed custom CMS workflows that cut publishing friction for the editorial team
  • Implemented the article publishing system with rich media support
  • Own Sanity CMS infrastructure and content modeling
  • Integrated ad placements and analytics tracking across the site

Key features

  • Editorial content management
  • Game reviews and previews
  • SEO-optimized article pages

Metrics

52KMonthly active readers
124KMonthly page views
Ongoing retainerEngagement

Tech Stack

Next.jsTypeScriptReactSanity CMS
Website

My Own Products

Three iOS apps and one SaaS that I design, build, ship, market, and bill for myself. It's why I'll ask about your conversion funnel and your unit economics, not just your feature list.

Chingu screenshot

Chingu

iOS

Learn Korean by actually talking. Real-time voice conversations with AI companions that correct you as you go.

Role

Solo Founder & Engineer

What I shipped

  • Built real-time streaming voice conversation on OpenAI's Realtime API — the hard part is latency, not the API call
  • Ran all AI calls through Supabase Edge Functions so no API key ever ships inside the app
  • Built a conversational system with 8 distinct companion personalities and memory across sessions
  • Implemented live grammar correction with inline explanations mid-conversation
  • Built spaced-repetition flashcards generated from what the user actually said
  • Shipped subscription monetization with RevenueCat

Key features

  • Real-time voice chat with AI companions
  • Live grammar corrections
  • Spaced repetition from conversation context
  • Adaptive difficulty (beginner → TOPIK prep)

Metrics

4.8★App Store rating

Tech Stack

React NativeExpoTypeScriptOpenAI Realtime APIWhisperElevenLabsSupabase Edge FunctionsRevenueCatPostHog
App StoreWebsite
NomadBudget screenshot

NomadBudget

iOS

Native iOS travel spend tracker with a home screen widget. Built in Swift, not React Native.

Role

Solo Founder & Engineer

What I shipped

  • Built fully native in Swift — no React Native — to get the widget and system integration right
  • Shipped a WidgetKit home screen widget with live spend totals
  • Designed the multi-currency data model and offline-first local storage

Key features

  • Home screen widget
  • Multi-currency tracking
  • Trip-based organization

Metrics

100% SwiftWritten in

Tech Stack

SwiftSwiftUIWidgetKit
App Store
Corgi screenshot

Corgi

iOS

AI journaling and mood tracking. Talk to it, and it writes the journal entry for you.

Role

Solo Founder & Engineer

What I shipped

  • Built offline-first architecture on WatermelonDB — the app works fully with no connection and syncs later
  • Ran two AI providers side by side (OpenAI and Gemini) to trade off quality against cost per feature
  • Built mood tracking with visual trends over time
  • Wired up Sentry crash monitoring and RevenueCat subscriptions

Key features

  • Conversational journaling
  • Fully offline-capable with background sync
  • Mood tracking and analytics

Metrics

4.3★App Store rating

Tech Stack

React NativeExpoTypeScriptOpenAIGeminiWatermelonDBSentryRevenueCat
App Store
ReelCarousel screenshot

ReelCarousel

Web
Live · I run this business myself

A SaaS I built and run solo: paste an app store link, get a finished TikTok carousel, and auto-post it on a schedule.

Role

Solo Founder & Engineer — design, build, billing, growth

What I shipped

  • Built the full product solo: auth, generation pipeline, editor, scheduler, billing, admin
  • Integrated TikTok's official API end to end — OAuth, publishing, analytics, account stats
  • Shipped subscription billing with Polar and LemonSqueezy, including webhooks and a customer portal
  • Built an AI image-generation pipeline on Gemini with a job queue and worker
  • Designed a first-run onboarding funnel and instrumented the whole thing in PostHog
  • Wrote and ranked the SEO content that brings in signups

Key features

  • App-store-link → finished carousel in ~30s
  • Scheduled auto-posting to TikTok
  • AI image generation and template library

Metrics

Me, soloBuilt & operated by
Polar + LemonSqueezyBilling in production

Tech Stack

Next.jsTypeScriptTailwindSupabaseOpenAIGeminiTikTok APIPolarPostHog
Website

Also on the App Store

NomadWalletMulti-currency expense tracker for digital nomads
TripWiseGroup travel spending with expense splitting
BudgyMinimal category-based budget tracker
Little MomentsBaby milestone and memory journal

How I Work

01

Discovery

We discuss your idea, goals, and target users. I help scope the MVP so you ship fast without cutting corners.

02

Design & Build

I design the UI and build the app. You get a deployable TestFlight build every week — so you never have to guess whether we're on track.

03

Launch

I handle App Store submission, review guidelines, and deployment. I've been through the rejection process enough times to route around it.

04

Support

Post-launch bug fixes, feature updates, and monitoring. My oldest client app shipped in 2021 and I still push updates to it.

What I Do

Mobile Development

Cross-platform iOS and Android in React Native — and native Swift when the job needs widgets, system integration, or raw performance.

AI Integration

Real-time streaming voice, vision, and chat on OpenAI, Gemini, and Whisper — with keys behind a server, never shipped inside the app bundle.

Monetization

StoreKit, Play Billing, RevenueCat, Polar, LemonSqueezy — all running in production today. Subscription edge cases are where most apps quietly lose revenue.

End-to-End Delivery

From wireframes to App Store launch to the analytics that tell you if it worked. One person, no handoffs, no account manager in between.

Ready to build your app?

Tell me what you're building and I'll reply within 24 hours — usually with a question about scope rather than a sales pitch.

Send an email

Based in Seoul (KST). I keep overlapping hours with US and European clients and reply within one business day.