A game where you tap all the balls to make them disappear. There are rules for the order of erasing. Finding the order is the key to the game.
This is a cassette player for albums.I have reproduced experiences of listening music with a cassette tape.
An app to learn the basics of ladder logic, which is a graphical programming language. Free version available.
This is a slider for low volume that allows more precise control than the iPhone's side buttons.
Quiz to guess the state of the United States. The surrounding states are shown. Guess based on that.
Quiz to guess the prefecture of Japan. The surrounding prefectures are shown. Guess based on that.
This app helps you learn how to calculate questions about distance, time and speed with animation in which a car is running.
Given two of the distance, time, or speed, you can calculate the other one.
This is a music sequencer using numeric data. This app is for making MIDI data to send to an another app applied to virtual MIDI.
This is an application that actually tries to do the Monty Hall problem. Two people play the role of a host and a challenger. The player (the host) chooses the winning door, which gives a more reliable game.
This app displays kanji, emoji, or other characters in large size. I made this to help you look up kanji you can't write. This is especially useful when you use an iPad and display this app on one of the two windows.
The app analyzing the popularity of kanji.
This is an app for Kyotsu Test, the test widely used in Japanese university entrance exams, dealing especially with probability problems in mathematics.