へいらっしゃい！ - おすしかずあわせ

This is a mobile-friendly web app that records study time and visualizes it with a GitHub-style heatmap. No login required, no server required. All data is saved in the browser's LocalStorage.

A perfect Japan map quiz for school preparation, review, and test preparation! ✏️ With a game-like format of just 10 seconds per round, even kids who struggle to sit at a desk will be captivated and challenged! It's a helpful app where you can master Japanese geography while having fun!

A site where you can visit over 1,000 historical spots featured in textbooks and reference materials by browsing them on a map

It is a web application that allows you to learn system English vocabulary from a personal computer or smartphone.

From Sekigahara and Okehazama to Red Cliffs. A free site where you can view historic battles in 3D picture scrolls of approximately 3 minutes.