My Senpai

About My Senpai

My Senpai is an independent studio that makes four free apps for people learning Japanese, and the free guides and browser tools on this site. This page covers what each app is for, how we make the apps, how we write the guides, what the site collects and how to reach us.

Last reviewed 2 November 2026 · By the My Senpai team

What is My Senpai?

My Senpai is one studio making four Japanese learning apps, each for one stage: kana, speaking, reading and vocabulary. All four are free with ads, run on Android, iPhone and in a browser, and none of them asks you to sign up first.

Kana Challenge

A hiragana and katakana app: a 30-day course in both scripts for complete beginners: five new characters a day, a quiz that decides when you move on, animated stroke order, and tracing and writing that mark each stroke. How Kana Challenge works.

FluencyTool

A Japanese speaking practice app: you hear a Japanese sentence, say it back, and speech-to-text shows which words came through. Sentences are graded over 25 sub-levels from JLPT N5 to N1, and the Kanji Tower teaches the 1,026 kanji of Japanese elementary school. How FluencyTool works.

YoMoo

A Japanese reading app with furigana: news, 325 JLPT passages, 500 Aozora Bunko texts or your own text, with furigana, a JLPT colour on every word and the meaning one tap away. Saved words come back for review. How YoMoo works.

My Senpai Crossword

A daily Japanese crossword: a new 20×20 grid every day with English clues and JLPT answers from N5 to N1. You type the reading in romaji and the grid fills in hiragana, alone or live with another learner. How the crossword works.

How are the apps made?

• Speaking scores check words, not accent. FluencyTool and Kana Challenge use speech-to-text: the app writes down what it heard and compares it with the target, so the score shows which words or syllables came through. It does not rate pitch accent, vowel length or how natural you sound; for pitch on its own there is the free Pitch Accent Lab.
• Levels come from JLPT word lists. FluencyTool grades its sentences over 25 sub-levels from N5 to N1. YoMoo colours each word by the JLPT level of the word itself, not its first kanji. Every crossword answer is a JLPT word, 7,753 across N5 to N1.
• Dictionary data is open. YoMoo's built-in dictionary has more than 250,000 words and readings from JMdict and JMnedict, the open Japanese dictionary projects (CC BY-SA 4.0).
• One part is written by AI, and labelled. The Easy version of each YoMoo news article is written by AI from the original article, with everyday words and plain grammar, and it is labelled Easy in the reader. The Original is always one tap away.
• Free with ads; paying is optional. FluencyTool and Kana Challenge have one optional one-time purchase that removes the ads. My Senpai Crossword's Ad-Free and Unlimited are one-time purchases. YoMoo has an optional monthly or yearly subscription that removes ads and the article limit. None of the apps needs an account; in FluencyTool an account is only for cloud sync.
• Every release is listed. Each app has an Updates page with what changed in each version: FluencyTool updates, Kana Challenge updates, YoMoo updates, My Senpai Crossword updates.

How are the guides written?

• Every guide is written and checked by the My Senpai team, and signed as the team.
• Comparison pages check prices on the day and say when: the Duolingo alternatives for speaking Japanese compares seven apps with "Prices checked November 1, 2026".
• When one of our apps is in a comparison, the page says it is ours and lists its limits plainly: in that comparison, FluencyTool has no tutor and needs a connection for its speech-to-text check.
• No affiliate links, and no app or tool pays to be listed. The Japanese Learner's Map lists the tools people use at each stage from kana to N1, and most of them are not ours.
• Where a page can let you practise, it does: a kana quiz, a furigana passage you can switch on and off, a searchable JLPT N5 vocabulary list with audio, and JLPT grammar lists from N5 to N1.
• Store reviews are quoted as written, with the reviewer's first name and initial, the stars, the store and the month. Ratings are shown with their source and the date we checked them, as on the FluencyTool reviews page.
• Corrections are welcome: email fluencytool@my-senpai.com with the page and the line. Many of YoMoo's reading fixes started as an email.

What does this site collect?

• You can read the site and use its tools without an account, and without giving a name or email.
• On your first visit a cookie banner lets you accept or reject analytics and advertising cookies, or choose each kind. Google Analytics, loaded through Google Tag Manager, records pages viewed, how you arrived and clicks on store links.
• The read counter on articles sets no cookie, keeps only a count per article and day, and does not count visits that send Do Not Track or Global Privacy Control.
• Article comments ask for a name and the comment, not an email address, and every comment is checked before it appears.
• We do not sell personal information.

The full details, including every service that processes data, are in the website privacy policy. Each app has its own policy: FluencyTool, Kana Challenge, YoMoo and My Senpai Crossword.

How do I contact My Senpai?

Email fluencytool@my-senpai.com for questions, bug reports, a wrong reading, a privacy request or press. For a bug or a wrong reading, the word and the sentence it appeared in are the fastest way to a fix.

My Senpai is also on YouTube (@MySenpai1), Instagram (@mysenpailearnjapanese) and X (@MySenpai111).

Where can I get the apps?

All four are on Google Play and the App Store, and each has a browser version. The links to both stores are on each app's page.