Is Fluency Tool free?

Yes. All core learning features — Echo Fluency speaking sessions, flashcards, grammar guide, and vocabulary games — are completely free. There is an optional one-time purchase to remove ads permanently.

How does the spaced repetition system work?

Fluency Tool has two independent SRS systems. Flashcards use the SM-2 algorithm (the same one behind Anki) with Again/Hard/Medium/Easy ratings. Speaking sentences use a custom algorithm with an e-factor and a 4x mastery bonus after 5 correct repetitions.

★ Free Android App · JLPT N5–N1

Complete Japanese Learning SystemStop Just Studying Japanese.
Start To Actually Speak Japanese.

Name: Fluency Tool
Availability: InStock
Author: My Senpai

Build real speaking confidence through Echo Fluency shadowing — training your rhythm, pitch accent, and muscle memory. Flashcards, a full JLPT grammar guide, and vocabulary games tie everything into one personalized learning program.

Best for learners who can already read hiragana and katakana. Not there yet? Start with Kana Challenge →

▶ Download Free How it works ↓

★ 4.8 Rating

🌐 Multi-language UI

🔒 Free Core · No Subscription

Fluency Tool dashboard showing daily goal, activity chart and roadmap

Echo Fluency speaking session with recording indicator

Flashcard deck manager showing SRS status badges

JLPT grammar guide showing N3 pattern with example sentences

JLPT roadmap showing remaining sentences across 5 sub-levels

Grammar guide N5 content with example sentences and audio

Reading analyzer breaking down Japanese text

Dashboard — Daily goal & progress charts

JLPT Levels

Content Sub-Levels

Learning Modes

SRS Systems

⚙ The System

Four Tools. One Fluency Loop.

Most Japanese apps isolate one skill and leave you to figure out the rest. Fluency Tool builds four skills in parallel — and each one sharpens the others.

🎙️

Echo Fluency
Speaking Engine

Listen to a native Japanese sentence, repeat it, and hear your own voice played back. Speech-to-text grades you instantly. Sentences you struggle with re-queue automatically. No button to press — just speak.

Google Cloud TTSSTT EvaluationCustom SRS

🗂️

SM-2 Flashcard
Vocabulary System

Anki-compatible SM-2 scheduling. Rate cards Again, Hard, Medium, or Easy — and the algorithm calculates exactly when you need to see each word again. Long-press any kanji for a full on'yomi, kun'yomi, and meaning breakdown.

SM-2 AlgorithmKanji LookupCloud Sync

📚

JLPT Grammar
Guide N5–N1

Every JLPT grammar pattern from N5 through N1 — with native audio on every example. Tap any pattern to take an interactive quiz. Track your status as Learning, Reviewing, or Mastered.

All 5 LevelsNative AudioSRS Tracking

🎮

Vocabulary Games
& Crosswords

Play vocabulary matching and Speed Tap games built from your own flashcard decks. Plus Japanese crossword puzzles — so the words you're actively studying get reinforced in a completely different way.

Your Own DecksSpeed TapCrossword

🎙 Echo Fluency

The Fastest Path to
Speaking Japanese Confidently and Naturally

Shadowing is what professional language learners do: listen to native audio and immediately repeat it. Echo Fluency automates the entire cycle — building your confidence, rhythm, pitch accent, and muscle memory hands-free, every day.

Native Sentence Plays

A JLPT-appropriate sentence appears with furigana. Google Cloud TTS plays high-quality native audio. You listen.

Auto-Record Starts

The microphone opens automatically after playback. Just repeat what you heard. No tapping required.

Your Voice Plays Back

Hear yourself immediately after speaking. The gap between your output and the native model becomes obvious — and that's where improvement happens.

Instant Evaluation

Speech-to-text grades your pronunciation. ✅ Correct = next sentence. ❌ Incorrect = re-queued until you get it right.

SRS Schedules Your Return

Master a sentence five times and the review interval multiplies by 4×. You spend time on sentences that need work, not ones you already own.

Three Recording Modes

Echo Fluency (Auto) — App runs the full cycle. Recommended.

Timed Mode — TTS plays, then a timed recording window opens.

Hold to Record — Press and hold the mic. Full manual control.

Echo Fluency active recording session showing sentence with furigana and microphone indicator

Content Structured by JLPT Level

Advanced

5 sub-levels · complex grammar & literary forms

Upper-Intermediate

5 sub-levels · nuanced expression & reading fluency

Intermediate

5 sub-levels · everyday conversation & conjunctions

Elementary

5 sub-levels · basic sentences & common patterns

Beginner

5 sub-levels · foundational vocab & survival phrases

25 content buckets total — your Roadmap tracks real progress across all sub-levels

🗂 Flashcards

Vocabulary That Actually Sticks

SM-2 spaced repetition — the same algorithm powering Anki — shows you each card at precisely the right moment. Spend zero time on vocabulary you already know.

How SM-2 Works

Rate → Schedule → Review at the Perfect Moment

🔴

Again

Card reset to Learning. Short interval. Ease factor drops.

🟠

Hard

Interval shrinks. Stays in Learning. Ease factor drops.

🟡

Medium

Standard SM-2: interval = prev × ease factor. Progresses normally.

🟢

Easy

Interval extends further. Ease factor rises. Heads toward weekly reviews.

💡 After 5+ correct reviews, a card enters mature territory with multi-week intervals. You stop wasting time on vocabulary you've already mastered.

Everything in the Deck System

✓JLPT Preset Decks — Import N5–N1 vocabulary instantly on first launch

✓Custom Decks — Create cards with word, reading, definition, and example

✓Kanji Long-Press — On'yomi, kun'yomi, and English meanings from KanjiAPI

✓SRS Status Badges — New, Due Now, and Later-Today counts at a glance

✓Furigana Toggle — Show or hide hiragana readings above kanji

✓Cloud Backup — Firebase sync keeps your decks safe across devices

Deep Feature Spotlight

Kanji Breakdown on Demand

Long-press any Japanese word during a flashcard session to open a bottom sheet showing the full Kuromoji morphological breakdown — word definition, reading, and a character-by-character kanji analysis from KanjiAPI.dev.

音読み On'yomi

Chinese-derived reading

訓読み Kun'yomi

Native Japanese reading

名乗り Names

Name readings

Meanings

English definitions

📊 Dashboard

Open the App. Know Exactly
What to Do Next.

No guesswork. No decision fatigue. The Dashboard tells you where you stand and what needs your attention right now.

📅

Daily Goal Tracker

Sentences completed vs. your daily target. A progress bar turns green when you hit your goal. Flashcards ready shown at all times.

📈

Activity Chart

Bar chart of daily sentence completions over the past 7 or 30 days, with your goal line. Visualize your consistency at a glance.

🗺️

JLPT Roadmap

Horizontal bar chart of remaining new sentences across all 25 sub-levels. Navigate between N1–N5. Your current position highlighted in blue.

🔔

Study Reminders

Configurable daily notifications to keep your streak alive. Set once and forget. Revisit anytime from the Dashboard.

⚙️

Configurable Settings

JLPT level, sub-level, TTS voice, sentence speed, recording mode, dark mode, study goal — adjustable before every session.

☁️

Cloud Data Sync

Firebase-backed backup for flashcard decks and SRS progress. Restore on any new device in one tap. Anonymous auth — no account needed.

Fluency Tool dashboard showing activity chart and daily goal tracker

👤 Who It's For

This App Was Built For You If…

🌱

You can read hiragana and katakana

Set your level to N5 Sub-level 1. The beginner course covers foundational vocabulary and survival phrases, with furigana on by default to keep you moving.

🎓

You're preparing for JLPT

All content is organized by JLPT level. Use the grammar guide and flashcard decks to drill the patterns that appear on the exam.

🗣️

You can read Japanese but can't speak it

Echo Fluency is built for exactly this problem. You already have the vocabulary — you just need your mouth to catch up with your eyes.

📺

You're an anime or manga fan

Stop relying on subtitles. Shadowing native audio and building vocabulary through spaced repetition is the shortest path to understanding what you're actually hearing.

✈️

You're travelling to Japan soon

The N5 beginner course includes a survival track — essential phrases and vocabulary for travelers who need immediate, practical Japanese. Arrive with more than just gestures.

🏔️

You're pushing toward N1

Echo Fluency at native speed, complex grammar patterns, advanced conjunctions and literary forms — the Roadmap shows exactly which N1 sub-levels still need work.

📖

Not reading hiragana and katakana yet?

Fluency Tool is designed for learners who can already read hiragana and katakana. If you're not there yet, Kana Challenge is the recommended starting point — a dedicated 30-day course to get you reading both scripts fluently before you dive into speaking practice.

Start with Kana Challenge →

📱 Inside the App

See It In Action

Real screens from the app. Clean, distraction-free, built for focused daily sessions.

Fluency Tool dashboard with activity chart and daily goal

Flashcard deck manager with SRS status badges

JLPT grammar guide with N3 pattern examples

Flashcard study screen with SM-2 rating buttons

Speed Tap vocabulary game built from flashcard decks

JLPT roadmap with 25 sub-level progress bars

Japanese crossword puzzle using vocabulary from active decks

Correct answer dialog after completing a grammar quiz

Reading analyzer breaking down Japanese text with furigana and definitions

Fever Pitch fast-paced vocabulary matching game

話す聞く読む

Build Confidence, Rhythm & Pitch Accent.
One App. Every Day.

Echo Fluency trains your speaking from the inside out — muscle memory, natural rhythm, and real pronunciation. The core app is free. The download takes 30 seconds.

▶ Download Free — Android

Free core app · Optional one-time purchase to remove ads · No subscription

★ Reviews

What Learners Are Saying

★★★★★

"Really good app for speaking Japanese! Great and simple app for practising Japanese speaking. Listen to each phrase and repeat it, and thanks to the text-to-speech function, the app checks that the pronunciation is correct."

▶

Google Play User

5-star review

★★★★★

"I am learning Japanese and it really helped me. Very useful app and also clean UI design."

▶

Google Play User

5-star review

★★★★★

"Very helpful, I genuinely wanted to learn Japanese since I started watching anime. This app helps me navigate native Japanese phrases."

▶

Google Play User

5-star review

★★★★★

"I really enjoy this app a lot and I cannot believe it is free. TIP: If you hold your finger down on the Kanji, it will explain each one to you individually. I hope the developer continues to look for grammatical errors and bugs, because this could be the best Japanese learning tool on the app store."

▶

Google Play User

5-star review

★★★★★

"Best support I ever received! The mic wasn't working properly and the dev fixed it almost immediately! Amazing app for shadowing!"

▶

Google Play User

5-star review

★★★★★

"Really good app for speaking Japanese! Great and simple app for practising Japanese speaking."

▶

Google Play User

5-star review

? FAQ

Frequently Asked Questions

Everything you need to know before you download.

Is Fluency Tool completely free?+

Yes. Echo Fluency speaking sessions, all flashcard features, the full JLPT N5–N1 grammar guide, vocabulary games, and crossword puzzles are completely free. There's an optional one-time in-app purchase to remove banner ads — the full learning system costs nothing.

What JLPT levels does Fluency Tool cover?+

Fluency Tool covers all five JLPT levels — N5 (absolute beginner) through N1 (near-native advanced). Each level is divided into 5 sub-levels, giving you 25 distinct content buckets. The Dashboard Roadmap chart shows your remaining new sentences across all 25 sub-levels so you always know exactly where you stand.

What is Echo Fluency and how does it work?+

Echo Fluency is the app's core speaking mode. It plays a native Japanese sentence via Google Cloud TTS, automatically starts recording your voice, plays your recording back, then uses speech-to-text to compare your pronunciation to the original. Correct sentences are scheduled for later review. Missed sentences re-queue immediately. The whole cycle repeats hands-free.

How does the spaced repetition work?+

Fluency Tool runs two separate SRS systems in parallel. Flashcards use the SM-2 algorithm (the same one powering Anki) with Again / Hard / Medium / Easy ratings that adjust review intervals automatically. Speaking sentences use a custom algorithm where correct answers extend the interval by your e-factor, and mastering a sentence five times triggers a 4× interval bonus.

Do I need prior Japanese knowledge to start?+

None. Set your level to N5 Sub-level 1 and the app starts with foundational vocabulary and simple sentence structures. Furigana displays above kanji so you can read everything even before you know any characters. The onboarding wizard walks you through every preference before your first session.

Does the app work offline?+

Flashcard study, vocabulary games, and crossword puzzles work fully offline. Echo Fluency speaking sessions require an internet connection for Google Cloud TTS audio playback and speech-to-text evaluation. The grammar guide loads web content and requires connectivity.

Can I use Fluency Tool alongside Kana Challenge?+

Absolutely — they're designed as a progression. Kana Challenge gets you reading Hiragana and Katakana fluently in 30 days. Once you know kana, Fluency Tool's Echo Fluency sessions, flashcards, and grammar guide make full use of that foundation as you move through N5 to N1.

🌐 My Senpai Ecosystem