What a Designer Learned While Launching an App: The 90% Outside Design
1. A quiz where a career grows instead of a score
Capped is an app that connects knowledge of cricket and football to an experience of building up records like a real player’s career.
- Each time you answer correctly, career stats such as matches played, runs scored, and averages accumulate.
- The feeling of lasting growth, rather than a one-time score, became the basis for the game’s play and reward design.
- The sound and motion of the countdown, the timer just before the end, and trivia during loading shaped the game’s rhythm.
- Cheer animations appeared only for rare achievements to preserve the meaning of the reward.
2. Implementing with AI, and refining with a designer’s judgment
While Claude helped with implementation, the author focused on the experience users feel and the key decisions.
- The app was built with Expo and React Native, and Supabase was used to set up authentication and leaderboards.
- EAS was used for builds and deployment, and PostHog was used for usage analytics.
- Even in vibe coding, the role of understanding how the app works and judging its completeness remained.
- The starting point suggested was also a small screen that actually works on a real phone.
3. The quality of a quiz is determined by the accuracy of its questions
In a quiz, a single incorrect fact can shake trust in the entire product.
- Expressions like “only,” “first,” and “most” were verified intensively.
- Records that had once been true but had already been broken, plausibly made-up statistics, and anecdotes with no source were filtered out.
- After verification, the app included 394 cricket questions and 383 football questions.
- Because records keep changing, content verification is also a maintenance task that continues after launch.
4. What completed the launch was preparation outside the screen
The author reflects that design felt like about 10% of the overall effort, and the rest went into verification and launch preparation.
- They prepared a privacy policy, account deletion features for the app and web, a report of data collection details, and a content rating questionnaire.
- In a 14-day private test with more than 12 testers, problems on real devices were discovered.
- They fixed button cutoffs on small screens, login errors, and crashes that occurred during longer play sessions.
- Based on the improvements made in testing and the results of stability verification, they applied for production.
- The lesson remains that review preparation after screen completion and the time for testing must be included in the launch schedule.
