Software studio · Japan

Apps that make
study and work lighter.

Plusminus Lab is a one-person software studio in Japan. Right now we are building “Kakomon Note”, a past-exam study app for the Japanese bar exams with AI-assisted grading. We also make games, automate business tasks, and take on contract work.

Explore the focus Start a conversation

↓A closer look

00 / RIGHT NOW

What we are building

In development
Kakomon Note (過去問ノート)
An Android study app for the Japanese bar exams: practice past short-answer and essay questions, review explanations with the cited statutes, and get AI-assisted feedback on essay answers. Preparing for release on Google Play.
Ongoing
Games and interactive experiences
Small games and playful interactions, built and refined by one developer.
Ongoing
Business automation and contract work
Practical tools that remove repetitive work, plus CSV and template services on Coconala and Gumroad.

01 / THE FOCUS

Two directions. One considered approach.

From playful interactions to everyday workflows, the aim is the same: make software that feels clear, useful, and purposeful.

01PLAY & EXPERIENCE

Game development

Creating interactive experiences and exploring the craft of making something engaging.

View the approach

02TOOLS & WORKFLOWS

Business automation

Creating practical tools that simplify repetitive work and make everyday processes easier to follow.

View the approach

02 / THE PRACTICE

Independent by design.

Established in September 2026, a self-funded sole proprietorship in Japan working on games, business tools, and contract projects. The approach starts with a clear problem, a manageable scope, and room to learn.

About the practice

Keep it clear. Make it matter.

PURPOSE BEFORE COMPLEXITY

03 / THE NEXT STEP

Have something in mind?

An idea, a recurring task, or a question about the focus of the practice — the contact page is the place to begin.

Start a conversation

Apps that makestudy and work lighter.