Anki is a powerful, open-source flashcard program renowned for its effective spaced repetition system (SRS). It isn't a language course itself, but a highly effective tool for memorizing vocabulary, phrases, or grammar rules that you input yourself or download from shared user-created decks. Its high degree of customization allows for rich cards with audio, images, and cloze deletions. While its interface can be unintuitive for new users, its effectiveness for long-term retention is largely considered unparalleled for dedicated learners.

Lingopie champions the idea of learning a language through authentic media. The platform provides a library of TV shows and movies in your target language, enhanced with interactive dual-language subtitles. Users can click on any word for an instant translation and add it to a flashcard deck for later review. It excels at improving listening comprehension and exposing learners to natural dialogue and culture. While it promotes passive learning and lacks structured grammar or dedicated speaking components, it is an excellent and engaging resource for intermediate learners.