Klappa is a free spaced repetition app for students with exams where forgetting is expensive. It opens your Anki decks with each card's schedule, reviews them on FSRS-6, and studies four ways: Flashcards, Learn, Write and Test. Included free: Cortex, a study AI that cites a curated medical library; Live, in-class quizzes students join from their phones; and an MCP connector for Claude and ChatGPT. Web and Mac (offline). No ads, no paid tier.