Gothic-cha is an AR-based mobile application that reimagines how users interact with Gothic architecture during site visits. By scanning structural elements in real time, users receive layered commentary through augmented reality overlays, animated illustrations, and contextual text. The app transforms architecture into an interactive interface—each vault, rose window, or flying buttress becomes a scannable node for exploration. Designed around multimodal feedback and intuitive UX, Gothic-cha enables users to learn without leaving the experience. With features like daily content, bookmarking, and community interaction, the app bridges physical presence and digital depth, creating an immersive and culturally enriched platform for Gothic discovery.