Travel, exams, video, games, focus. The fields may look unrelated, but the way they are built is the same. Only real problems faced by my family or me—built and refined until the result feels right. All released apps are free to get started with.
Places to sleep, places to charge, and scenery worth a stop—all on one map.
I turned the experience of driving through all 47 prefectures with my family into an app. It helps you decide “where will we sleep tonight?” before the sun goes down.
Apps that support families through the daily reality of entrance-exam preparation. Gokaku Quest covers three subjects, and BuddyTalk can also be used by adults returning to study.
Geography, history, and civics—all 53 units.
Japanese middle-school entrance-exam social studies is divided by unit, so you can repeat only the areas you struggle with. Four-choice quizzes and illustrations leave a clear sense that you have actually learned the material.
4 fields, 28 units, over 2,000 questions.
Biology, earth science, physics, and chemistry, organized by unit. Because you can also raise a mascot, continuing to study becomes part of the fun. Achievement tests let you measure your progress.
Learn with both your eyes and your ears.
Learn kanji, vocabulary, proverbs, and grammar with text-to-speech. Even when you cannot look at the screen, you can keep studying by listening.
Everyday Japanese for life in Japan.
A Japanese-learning app for technical interns, Specified Skilled Workers, permanent residents, international students, and others. It includes 72 units and 4,320 questions across four areas—vocabulary, characters, grammar, and conversation—with furigana and romaji. The interface supports 9 languages.
Make mistakes. No one will laugh.
An English-conversation app where you talk with AI partners with different personalities. It evaluates pronunciation, so you can speak without worrying about mistakes. It also works well for adults returning to English study.
Turn forgotten photos and videos into something worth sharing.
Choose your photos. Let the app do the rest.
AI handles the structure, narration, captions, and BGM to produce a reel ready to post. No editing expertise is required. Narration can be selected from 15 languages.
A game that builds strategic thinking and vocabulary while you play. Instead of making it feel difficult, we focused first on making it genuinely fun.
Simple rules. Winning takes thought.
A stick-taking strategy game set in a forest. The number of sticks you can take is fixed, but making your opponent take the final stick requires thinking ahead. Includes more than 100 levels.
Turn rote memorization into arcade fun.
A shooter where English words approach from space and you shoot them down. Words you miss collect in review mode, so the ones you struggle with appear again and again.
Tools that make it easier to focus without relying on willpower alone.
A tap on your wrist tells you when to switch.
An interval timer on Apple Watch that automatically creates clear blocks for focus and rest. Because you do not need to keep checking the screen, your concentration is less likely to break.
The fields vary, but I follow only three rules. Rather than increasing the number of products, I choose a volume that I can continue improving even after release.
Car Travel Concierge began from our own car-camping trips, and Gokaku Quest began from our family’s exam preparation. If we are not personally facing the problem, the product will not last.
I spend more time removing points of confusion than adding features. The standard is whether users can reach their goal within a few seconds of opening the app.
Publishing is not the finish line; the real work begins after people use it. Because it is independently developed, I can fix something the day after I notice it.
