Why I Chose to Build a Paid JLPT N5 Kanji Flashcard App with React Native
After building a few free learning apps, I realized something important: free apps often force unnecessary compromises. Ads, distractions, and feature bloat slowly dilute the original learning goal. When I decided to build JLPT N5 Kanji Flashcards, I intentionally chose to make it my first paid app.
The problem I wanted to solve was very specific. JLPT beginners struggle with kanji because they either study too much at once or rely on tools that are not aligned with the N5 syllabus. I wanted to build a focused app that respects the learner’s time and attention.
What the App Focuses On
Instead of doing “everything,” the app does one thing well.
📘 Covers only JLPT N5 kanji, nothing extra
🧠 Uses flashcards for active recall, not passive reading
🔁 Shuffle mode to avoid memorizing order
📱 Works fully offline, ideal for daily revision
🚫 No ads, no subscriptions, no distractions
The idea is simple: if a learner opens the app, they should be studying within seconds.
Why I Kept the App Minimal
As a developer, it’s tempting to add progress graphs, login systems, cloud sync, and analytics. I deliberately avoided all of that. For beginner kanji learning, simplicity improves consistency.
A paid model also changes incentives. Since users already paid, the app doesn’t need engagement tricks. It only needs to deliver value. This mindset influenced every design decision.
Tech Stack & Build Decisions
React Native allowed fast iteration with a single codebase
Expo (managed workflow) reduced setup and maintenance overhead
Local JSON files store all kanji data for reliability
No backend keeps costs low and performance high
Async Storage is used only where necessary
AI-assisted tools helped refine UI and logic, not replace thinking
Expo EAS Build handled Play Store deployment smoothly
This stack was ideal for a solo developer shipping a paid product.
What I Learned from Building My First Paid App
The biggest lesson was this: focus is a feature. Users don’t need more options — they need fewer obstacles. Building a paid app forced me to think like a learner, not just a developer.
JLPT N5 Kanji Flashcards is small by design, but that’s exactly what makes it useful.
Download the App
👉 Play Store: JLPT N5 Kanji Flashcards
