Pick The Best Card 💳

Never leave rewards on the table. Pick The Best Card tells you exactly which credit card to use at any store.

🌐 Live at pickthebestcard.com
📱 Download on the App Store

The Problem

You have multiple credit cards. Each one earns different rewards at different stores — 5% here, 3x points there, rotating categories that change every quarter. Keeping track of it all is a full-time job.

Pick The Best Card solves this: type where you're shopping, and it tells you which card in your wallet earns the most.

Features

• 🔍 Search any store — 500+ merchants across 42 categories with smart fallback for unknown merchants
• 📍 Location-aware suggestions — GPS-based nearby store detection; tap to instantly get the best card for where you are
• 🔎 Google Places autocomplete — when a merchant isn't in the database, Google Places fills in with automatic category mapping; merchants are auto-saved to the DB on first lookup
• 💳 Your wallet — add the cards you actually own; synced across web and iOS
• 🏆 Instant ranked recommendations — best card first, with effective % value for points cards
• 🔄 Rotating category support — Discover 5%, Chase Freedom Flex, and others tracked with active dates
• 💰 Points valuation — converts points to real dollar value (e.g. 3x Chase UR ≈ 6% value)
• 🛡️ Card protection benefits — shows car rental insurance and extended warranty coverage ranked by primary/secondary tier and coverage amount
• 🏨 Loyalty card accuracy — hotel/airline cards (Hyatt, IHG, Marriott, Hilton, Delta, United) earn bonus points only at their own brand, not competitors
• ⛽ Merchant-specific rates — e.g. Costco Anywhere Visa earns 5% at Costco Gas, 4% at other gas stations
• 🌐 Online vs. in-store — distinguishes online-only card benefits
• 🔗 Official benefit links — direct links to each card's benefits page

Monorepo Structure

pickthebestcard/
├── web/              # Next.js web app → pickthebestcard.com
├── mobile/           # Expo React Native iOS app
├── shared/           # Shared types + business logic (single source of truth)
└── crawler/          # Weekly benefit crawler (GitHub Actions)

Shared Package

shared/ contains all types and pure functions used by both web and mobile:

• Types: Card, Recommendation, Protection, MerchantMatch, MerchantTag, NearbyPlace
• Functions: formatReward, formatEffectiveValue, sortRecommendations, sortProtections, detectCoverageTier, googleTypesToCategoryName

Because Vercel only builds web/ and Expo only builds mobile/, the shared source is copied into web/src/shared/ and mobile/lib/shared/ at dev time. Both use a TypeScript path alias @pickthebestcard/shared that resolves to their local copy.

Stack

Web (web/)

• Framework: Next.js 14 (App Router)
• Auth: NextAuth v4 with Google Sign-In
• Database: Neon Postgres (serverless)
• Styling: Tailwind CSS
• Analytics: Vercel Analytics + Speed Insights
• Tests: Vitest (111 tests)
• Deployment: Vercel (root directory: web/)

Mobile (mobile/)

• Framework: Expo + React Native (Expo Router)
• Auth: @react-native-google-signin/google-signin (native SDK)
• Card sync: /api/mobile/cards endpoint (Google token auth)
• Tests: Jest (28 tests)
• Platform: iOS only

Crawler (crawler/)

• Puppeteer-based; runs on GitHub Actions every Monday 10:00 UTC
• Parses benefit pages via OpenAI GPT-4o-mini
• Covers: Chase, Amex (headful via Xvfb), Capital One, Citi, US Bank, BofA, Discover
• LLM extracts: fixed rewards, rotating rewards, car rental insurance, extended warranty
• Merchant-specific rates returned by LLM (e.g. "5% at Costco Gas, 4% elsewhere" → two entries)

Database Schema

Table	Rows	Description
cards	80	Credit cards with issuer, reward type, points value
card_benefits	315	Fixed + rotating reward rates; supports merchant-specific and category-level rates
card_protections	21	Car rental insurance + extended warranty with primary/secondary tier
categories	42	Spend categories (Groceries, Hotels, Gas Stations, etc.)
merchants	505	Known merchants with category and domain
merchant_tags	33	Multi-tag system: car_rental, extended_warranty_eligible
merchant_sightings	dynamic	GPS-discovered places, promoted to merchants daily
location_requests	dynamic	Rate limiting for GPS feature (100/day per user)
users	—	Signed-up users
user_cards	—	Cards saved per user

Cards Supported

80+ cards across all major issuers:

• Chase — Sapphire, Freedom, Ink, United, Marriott, Hyatt, IHG, Southwest, World of Hyatt
• American Express — Platinum, Gold, Green, Delta, Hilton, Marriott Bonvoy
• Capital One — Venture X, Venture, Savor, Quicksilver
• Citi — Double Cash, Strata Premier, Custom Cash, Costco Anywhere Visa
• Discover, US Bank, Bank of America, Wells Fargo — key rewards cards

Local Development

Prerequisites

• Node.js 18+
• A Neon Postgres database (free tier works)
• Google OAuth credentials

Web

git clone https://github.com/keremsahin1/pickthebestcard.git
cd pickthebestcard/web
npm install
cp .env.example .env.local
# Fill in: DATABASE_URL, GOOGLE_CLIENT_ID, GOOGLE_CLIENT_SECRET, NEXTAUTH_SECRET, NEXTAUTH_URL
npm run dev

Mobile

cd pickthebestcard/mobile
npm install
npx expo run:ios

Note: ios/ is gitignored (Expo managed workflow). Run npx expo prebuild --clean to regenerate it. Google Sign-In requires a native build — Expo Go is not supported.

Running Tests

cd shared && npm test          # 49 shared logic tests
cd web && npx tsc --noEmit && npm test   # 111 web tests
cd mobile && npm test          # 28 mobile tests

Environment Variables

Variable	Where	Description
DATABASE_URL	web, crawler	Neon Postgres connection string
GOOGLE_CLIENT_ID	web	Google OAuth client ID
GOOGLE_CLIENT_SECRET	web	Google OAuth client secret
NEXTAUTH_SECRET	web	Random secret for session signing
NEXTAUTH_URL	web	Your deployment URL
GOOGLE_PLACES_API_KEY	web	Google Places API (nearby + autocomplete)
OPENAI_API_KEY	crawler	GPT-4o-mini for benefit parsing

Deployment

• Web: Push to main → Vercel auto-deploys (root directory: web/)
• iOS: Archive via Xcode → upload to App Store Connect
  • Set ENABLE_USER_SCRIPT_SANDBOXING = No in Xcode Build Settings
  • Run npx expo prebuild --clean before archiving after config changes
• Crawler: Runs automatically on GitHub Actions every Monday; can be triggered manually via workflow dispatch
• Merchant promotion: Daily GitHub Action promotes GPS-discovered merchants from merchant_sightings to merchants table

Contributing

See CONTRIBUTING.md for setup instructions, test commands, and the mobile smoke test checklist.