Lerner

A mobile and desktop application for learning German, designed specifically for Russian speakers. Covers levels from A0 to B2 with a structured curriculum of 96 lessons.

Key Features

• Spaced repetition (SM-2) - vocabulary review with independent tracking for words, irregular verbs, articles, and conjugations
• 4 exercise types - multiple choice, text input, word order, and full sentence construction with progressive difficulty
• Error loop mechanic - mistakes trigger re-drilling from the error point, ensuring solid learning
• Built-in dictionary - browse, search, filter by part of speech, add words to review
• Text-to-speech - native pronunciation for all vocabulary
• Thematic situations - real-world scenarios: shopping, doctor, bank, government office
• Offline-first - all content stored locally, no internet required
• Dark/light theme

Architecture

The app uses a structured 5-stage lesson flow: theory, word learning, grammar check, sentence drills (100 exercises per session), and spaced repetition review.

Vocabulary database contains ~24,000 German words, curated using a custom Go TUI tool (Bubbletea) for interactive sorting and filtering of dictionary CSVs.

Cross-platform: Android, iOS, Linux, Windows, macOS.