Owing to the widespread use of location-Aware devices and the increased popularity of micro-blogging applications, we are witnessing a rapid proliferation of geo-Textual data. In this demonstration, we present iZone, an efficient system for determining influence zones over geo-Textual data. Specifically, iZone allows users to browse geo-Textual objects, evaluate the influence zones of specified geo-Textual objects, and obtain explanations of the evaluation results. The iZone system adopts a browser-server model. The server side integrates two types of spatial keyword search, namely top-k spatial keyword query and reverse top-k keyword-based location query, to support the functionality of the system. A variety of spatial indexes are employed to enhance the efficiency of the system. The browser side provides a map-based GUI interface, which enables convenient and user-friendly interaction with the system. Using a real hotel dataset from Hong Kong, iZone offers hands-on experience with influence zone evaluation in real-life applications.