Enabling a web application to call at least one native function of a mobile device includes accessing the web application by a browser of the mobile device. The web application includes at least one GUI element. The mobile device operates a listener module that is a TCP/IP socket listener listening for an address including a localhost IP address and a port number. Upon selection of the GUI element, a cross domain HTTP request is submitted by the browser to the listener localhost IP address. The listener module receives the request and calls the at least one native function in dependence on the received request.