Kiruko is a free iOS app that teaches you how AI actually works, from the ground up. Not "what is machine learning" surface-level stuff. Real depth: tokenization (BPE), self-attention (Q/K/V), transformer architecture, context windows, hallucinations, RLHF, RAG, and a full Generative AI module. Each concept is taught through interactive lessons with visual explanations, mini-games, and AI-graded exams (including speak-it-out and interview sections where you explain concepts in your own words).