SignTown is a web-based, real-time sign recognition game, where users take control of an avatar to communicate with other characters in sign language to get things done. The game employed an end-to-end open source platform for machine learning, TensorFlow^TM, to train the sign language recognition model. It enables users to learn and express themselves in sign language and to get feedback about their signing simply with a computer and a webcam. SignTown is designed around various common categories and themes. It also provides information about deaf culture in various regions. Users can enjoy the experience of signing into Hong Kong sign language and Japanese sign language in the game.