CAVOK: Study Buddy is a native Mac app for students with a textbook and a deadline. Drop in your own PDF and ask questions in plain language. CAVOK answers using only that book and cites the exact page. If it doesn't know, it says so, no guessing, no filled in gaps. Everything runs on your device by default. No account required. Turn on cloud mode with your own API key for deeper, adaptive answers. Nothing passes through us because we don't run servers. One-time purchase, $14.99.