Learning, talking, travelling, making. We turn the hard and tedious parts of everyday life into apps you actually want to keep using.
And for other parts of the day
App Store (Japan) public data and Gokaku! Quest course data as of October 25, 2026. Mochi is in review and not counted.
A study app born from our own family's entrance-exam years. Science, social studies, Japanese and math, plus real-estate, financial planning, bookkeeping, IT Passport, SPI3, Japanese, English and driving theory, in one app.
Level 40 and 50 questions are free; levels 60 and 70 and the full atlases are Pro. In-app purchases and ads.
Entrance-exam guides (Japanese): Science・Social studies・Japanese・Math・Memorization・FAQ
Talking, travelling, making, translating. Every app started as something we wanted to use ourselves.
Feel betterMochi
Chat with Mochi, a soft companion, by voice or text. On good days and cloudy ones, Mochi listens and answers with its face.
In App Store review, coming soon
Learn more →
TravelCar Concierge
A road-trip app born from a parent-and-child drive around Hokkaido. Roadside stations, RV parks, service areas, parking and hot springs on a single map.
CreateReel Make
AI turns the photos and short clips on your phone into a finished vertical reel. No editing skills needed.
ConnectVoiceLink AI Translator
A real-time interpreter that runs speech recognition, translation and summaries entirely on your iPhone or iPad.
LearnBuddyTalkTalk with AI until English comes out naturally. An English app focused on speaking practice.
LearnEnglish QuestGrammar, vocabulary and English exams, learned through quizzes and explanations.
LearnGokaku! FP QuestThe six areas of the Japanese financial planner exam, with illustrated guides and questions.
LearnWord BlasterWords fly at you as enemies. A vocabulary shooter for 10 languages.
PlayWood GolemA strategy puzzle built on the classic stick-taking game, with a golem who grows as you win.
FocusHacking TimerAn interval timer for Apple Watch that keeps a rhythm of focus and rest.
262 App Store ratings across all apps (Japan, as of October 25, 2026).
TrailFusion AI is the indie studio of Hiroaki Yuasa (Hiro). Facing entrance exams as a family, driving across Japan with the kids and building a camper van by hand: the troubles and the fun become apps.
Not apps, but the hobbies that started them.
An indie studio run by Hiroaki Yuasa. On the App Store, the publisher name is "hiroaki yuasa".
All apps are free to download. Some features and courses are in-app purchases; check the purchase screen in each app for details and prices.
Use the support page or email trailfusionai@gmail.com. App-specific terms and privacy policies are listed on the support page.
Several apps support English, including Reel Make, VoiceLink, Word Blaster and BuddyTalk. Gokaku! Quest is built around Japanese courses.
Gokaku! Quest is free to download.
In-app purchases and ads. Devices, courses and features vary by OS and version.
