Overview
Timón App is a mobile exam simulator for aspiring sailors preparing for official Spanish nautical licenses — PNB, PER, Patrón de Yate, and Capitán de Yate.
The app covers the full official question bank for each license, letting users practice at their own pace or run timed exam simulations that mirror the real test conditions. Results are scored instantly, and progress is tracked across sessions so users can focus on areas where they need the most improvement.
I built this to scratch my own itch — I was studying for a nautical license and found the existing tools either outdated or cumbersome. It also gave me a good excuse to go deep on React Native and Expo.
Features
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Full official question bank
All questions from the official DGM exam bank for PNB, PER, Patrón de Yate, and Capitán de Yate.
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Timed exam simulations
Simulates real exam conditions with time limits, question count, and a final score matching official criteria.
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Progress tracking
Per-topic success rates and session history help users identify weak areas and measure improvement over time.
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Practice mode
Untimed practice with immediate answer feedback and explanations, ideal for learning unfamiliar topics.
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Offline-first
The entire question bank is bundled with the app — no internet connection required to study or take exams.
Tech stack
- Framework
- React Native with Expo (managed workflow, SDK 55)
- Language
- TypeScript throughout (strict mode)
- Navigation
- Expo Router (file-based routing)
- State
- React Context — ResultsContext for test history, SubscriptionContext for RevenueCat
- Storage
- AsyncStorage for persisting test history
- Distribution
- EAS Build & Submit for App Store and Google Play