Where words become
yours
Your vocabulary, always with you. Nookab starts empty. Add words as you encounter them — on the train, in a book, during a conversation. Nookab tracks your mastery, flags weak spots, and adapts to your pace. No account. No subscription. No internet required.
Your Nookab, your way
Everything about Nookab is designed around what you control.
Your Words
Nookab ships empty — no pre-built word lists you didn't ask for. You add the words you encounter while reading, watching, or conversing. Every word in your vocabulary was added by you, for you.
Your Privacy
No accounts, no cloud required. Your vocabulary lives entirely on your device. No sign-up, no email, no password required. Your learning data stays yours.
Your Investment
Completely free, forever. No subscriptions, no in-app purchases, no locked features, no premium tiers. Every practice mode, every chart, every setting is available from day one. There is no catch.
Your Experience
No dark patterns, no fake scarcity, no engagement-for-engagement's-sake. Nookab doesn't use social feeds to distract you or leaderboards to guilt you. Every feature exists to help you learn.
Your Pace
Mastery over memorization. No timers, no speed scoring, no pressure. Words move through learning tiers based on your actual retention, not how fast you can recall.
Your Preferences
Set daily goals, choose your week start day, and enable learning tools like text-to-speech and special characters. Customize your learning experience the way you want.
Built for real learners
Every feature solves a problem a language learner actually faces. No bloat, no gimmicks, just what works.
Mastery-Based Spaced Repetition
Before each practice session, the engine classifies your words into buckets based on how well you know them. Words at risk of forgetting surface first, so you always practice what matters most. Unlike traditional SRS that locks words until their due date, Nookab never blocks you from practicing — the algorithm suggests, not commands.
Weak Word Detection
A word is flagged weak when you answer it incorrectly twice in a row, or when your accuracy drops below 60% after 5+ reviews. Weak words are automatically prioritized in practice sessions until they recover. To recover, a word needs 5 consecutive correct answers spanning at least two different days — we make sure when you master a word, you actually mastered it.
Detailed Statistics
Track your accuracy by word type, category, and over time. See your hardest words, most practiced, and activity over 14 days. Charts show progress at a glance — no need to dig through menus. Everything is computed locally, so stats load instantly even in airplane mode.
Excel Import/Export
Your vocabulary is yours — even if you leave. Export all your words before you go, and if you ever come back, import them and voila — everything is exactly where you left it. Full data portability. No data loss, no starting over.
Quick Sprint
Four one-tap practice shortcuts on the dashboard — no setup required. Quick Sprint auto-starts a 5-question Quiz from all your words. Today's Words focuses on words you added today. Mastery Boost targets low-mastery words. Clear Weak Words hones in on weak spots. Each shortcut has their own daily limits to keep practice focused and intentional.
Consistency Streaks
Track your daily learning streak with visual weekly dots. Active days are filled; inactive days stay muted. Build habits that stick with daily goals and progress tracking. The streak system uses a 7-day window — miss a day and the streak resets, creating a gentle accountability loop.
German Special Characters
Floating keyboard helper for ä, ö, ü, ß, Ä, Ö, Ü. Solves a specific input problem for German learners on non-German keyboards — reduces typing time from 1.5-2.5s per character (long-press menu) to ~0.3s (single tap).
Text-to-Speech
Hear pronunciation in German (de-DE) and English (en-US). Tap the speaker icon on any word to hear it spoken aloud. Uses dual-coding theory — information presented through both visual and auditory channels is retained better than either alone. Meta-analyses estimate 15-25% retention improvement with audio reinforcement.
Language Tips
Language-specific learning advice for English and German learners. Practical tips that help you understand grammar patterns, common mistakes, and cultural context. Daily insights — master the language, one tip at a time.
Daily Targets
Set a daily practice goal and track your progress throughout the day. The dashboard shows a circular progress ring that fills as you practice. Set it once, hit it every day.
Category Management
Organize vocabulary into semantic groups like "Travel," "Food," or "Business." Categories aid memory via chunking — words learned in a categorical context are recalled better when the same category is cued during practice. Create, edit, or delete categories anytime.
14-Day Activity Chart
Visual bar graph showing your daily practice over the last two weeks. See patterns in your learning habits — which days you practiced most, which days you skipped. Uses your configured week start day (Monday or Sunday) so the chart matches your calendar.
Your Words. Your Way.
Start learning in under 10 seconds. No accounts, no tutorials, no hassle.
Add Words
Encounter a new word? Tap + and add it with translation, article, and category.
Practice Words
Choose Flashcard, Quiz, or Spelling mode. The smart engine picks words that need attention.
Track Progress
Watch words move from Learning to Mastered. Weak words are flagged automatically.
Master Words
Words need 5 consecutive correct answers across 2 days to be mastered. No shortcuts.
Every vocabulary app had the same four problems
📓 Your vocabulary is stuck in notebooks
You collect words from videos, books, conversations — but they sit in a notebook you don't always have. Spare moments go unused.
📚 No app lets you practice only your words
Every app ships with 2,000 pre-built words you didn't ask for. Your own vocabulary gets diluted by someone else's word list.
💳 Paywalls block what actually helps
Spaced repetition, multiple practice modes, detailed stats — locked behind $5-15/month subscriptions.
📡 Internet dependency kills opportunistic learning
The moments you have free time — commutes, waiting rooms — are exactly when there's no signal. Cloud tools fail when you need them most.
Nookab is the answer to all four. It starts empty. You fill it with your words. It works offline. It's completely free. No account, no subscription, no catch.
Democratize vocabulary mastery by making scientifically-backed learning algorithms accessible to everyone — completely offline and free of distractions.
Every word, every way
3 practice modes. Unlimited ways to start.
Flashcards
See word, flip to reveal all its details at once — translation, article, examples, notes. Review everything about a word in one glance.
Quiz
Pick the correct translation from four options. Tests recognition — can you identify the right word from similar alternatives?
Spelling
Type the word from memory with no hints. The most challenging mode — full recall from scratch. Strongest evidence of true retention.
Quick Practice Shortcuts
Skip the setup — one tap and you're practicing.
Quick Sprint
5-question Quiz from all words
Today's Words
Focus on words you added today
Mastery Boost
Target low-mastery words
Clear Weak Words
Hone in on weak spots
Track your progress
Every word moves through mastery tiers as you practice. Watch your vocabulary grow.
Your data stays yours
No servers, no accounts, no tracking. Your vocabulary lives on your device, period.
100% Offline
Every feature works in airplane mode. No internet needed.
No Accounts
No sign-up, no email, no password. Just open and use.
Your Data Stays Local
Everything lives on your device. Nothing is uploaded to any server.
No AI Training
Your vocabulary is never used for AI/ML training. Never.
Frequently asked questions
Everything you need to know about Nookab.
Start building your vocabulary today
Free on Google Play. No account needed. Works offline.