Building 24 iOS Apps as a Solo Developer in Japan

Hey Indie Hackers! 👋 I'm Keisuke, a solo iOS developer based in Japan. I've been building and shipping iOS apps for several years, and I wanted to share my journey of creating 24 apps while working alone.

The Portfolio

My apps span multiple categories:

Productivity

• HieroNote - Hierarchical note-taking with built-in music player. Think WorkFlowy meets Spotify.

Games

• Idle Spirits - A meditative block-breaking game where you collect 57 mystical spirits. No competition, just zen.

Health & Fitness

• MyDailyEats - Food diary without calorie counting. Just categories and portion sizes.
• PMS Rage Tracker - Because sometimes you need to track the anger, not just the cycle.

Pet Apps (AnimalScale series - 14 apps!)

• Photo diaries for pet owners: BunnyScale, HamsterScale, CatScale, DogScale, and 10 more species.

AI-Powered

• KidsPlayAI - AI suggests nearby playgrounds and activities for kids
• LivabilityAI - AI analyzes neighborhood livability

Tech Stack

• Swift + SwiftUI (100% native)
• CloudKit for sync
• No backend servers (cost = $0)
• AdMob + StoreKit for monetization
• 35 languages supported via custom localization

What I've Learned

1. Niche beats general - My pet weight tracking apps found dedicated users who love their specific animals.
2. Privacy sells - "No account required, data stays on your device" resonates with users.
3. Less is more - MyDailyEats succeeds by NOT counting calories. The "missing feature" became the selling point.
4. Localization matters - Supporting 35 languages opened up markets I never expected.

Current Challenges

• Marketing is hard for a solo dev
• App Store discovery is basically zero without effort
• Balancing maintenance of 24 apps with new development

What's Next

• Launching on Product Hunt (preparing for this)
• Building community around the apps
• Exploring ways to monetize without compromising the user experience

Happy to answer any questions about building multiple apps solo, the Japanese iOS market, or anything else!

🔗 Links:

• HieroNote: https://keik.co.jp/hieronote/index-en.html
• Idle Spirits: https://keik.co.jp/idle-spirits/index-en.html
• MyDailyEats: https://keik.co.jp/mydailyeats/index-en.html