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.

Beelinguapp facilitates language learning through reading with its unique side-by-side text display. Users can read stories, articles, and songs in their target language while having their native language visible for reference. Each text is accompanied by "karaoke-style" audio that highlights the words as they are spoken, enhancing both reading and listening comprehension. While it doesn't offer grammar instruction or speaking practice, it is an effective and engaging resource for learners who enjoy story-based content and want to build vocabulary in context.