Public display systems are increasingly becoming part of the urban landscape, with systems being deployed in venues such as railway stations, shopping malls and city squares. Most public displays today are simple slide-show systems that broadcast content based on a pre-selected schedule. However, public displays envisioned in the near future will provide a rich platform for running diverse interactive applications with highly contextualized and personal- ized content. These applications will allow viewers to express their preferences both explicitly through interactive touch interfaces and implicitly using mobile handsets. This project explores the development of an Android mobile application that allows viewers to influence the content of the application displayed on public displays. The mobile application that has been developed is based on an HTML5 component that is the user interface in conjunction with native Android components that monitors locations of the mobile phone, implements the interaction with the displays using the WebSocket protocol and store users data.