Drapoz
App StoreFlags and capitals quiz. One daily challenge, identical for every player, a single attempt, ranked on time — deterministic seed, validated server-side.
- Role
- Solo developer — design, code, release
- Period
- 2025 — 2026
- Status
- App Store
The problem
Most quiz apps ask for an account before you have played a single round, and their "daily challenge" is generated on the device — which makes any leaderboard meaningless. I wanted a ranking that means something, without asking anyone to sign up.
The decision
A daily challenge that is the same for everyone, with no account behind it
The ten questions of the day are derived from the date through a deterministic seed, so every player in the world gets the same set in the same order. There is one attempt, recorded server-side, and ties are broken by elapsed time rather than by score alone.
Identity is a random identifier generated at install — never a hardware identifier. That is the decision the whole app hangs from: it makes a real leaderboard possible while collecting nothing personal, and it means a reinstall genuinely starts over rather than resurrecting a profile the player thought was gone.
The chain
Architecture
Shipped
- Défi du jour with server-validated single attempt and chrono tiebreak
- Two leaderboards: today’s challenge and all-time
- Three free modes — Quick Quizz, Quick Capital, Marathon (223 flags, 30 min)
- XP, levels and a daily streak
- System / light / dark themes, haptics, opt-in daily reminder
Screens
Next project
Valiz →