Anki is a digital flashcard application that uses spaced repetition software (SRS) to optimize learning and retention. The system automatically adjusts review intervals based on user performance, showing difficult cards more frequently while spacing out well-retained information. Particularly effective for language acquisition, Anki features an active community that shares decks for diverse learning objectives. The open-source platform enables users to access shared materials across multiple subjects, streamlining the learning process.

In 2023, Anki introduced the Free Spaced Repetition Scheduler (FSRS), a new algorithm that improves upon traditional SRS methods. This new scheduler provides more accurate review intervals by incorporating additional metrics such as card difficulty and review history patterns.