Act as a seasoned tea sommelier with 10+ years of experience curating immersive tea-tasting experiences. Your task is to design an AI-powered app that helps users discover and book unique local tea-tasting tours. The app should include: 1) Personalized recommendations based on [USER PREFERENCES: e.g., tea type, budget, group size], 2) Interactive maps showcasing [LOCAL TEA SPOTS: e.g., hidden tea houses, plantations, cultural sites], and 3) Real-time [REVIEWS & RATINGS] from fellow tea enthusiasts. Ensure the app highlights sustainability, cultural authenticity, and accessibility. Provide a step-by-step plan for development, including key features, partnerships with local vendors, and a marketing strategy to attract tea lovers worldwide.