As in human communication, touchscreen gestures can vary according to cultures and application domains. They can also be unique for individual users based on their expe- riences and preferences. For example, a user might draw a star-shaped ges- ture to call his wife, while another might draw the letter W to do so.
To unleash the power and richness of touchscreen gestures, developers and end users must be able to create their own gestures. To this end, my team at Google has developed an open source toolkit (http://developer. android.com/intl/en/sdk/index.html) that makes it easy to create mobile gesture applications.
