A system (1) for conducting commercial transactions comprises an application server (2) that hosts a software application that can be accessed by users to conduct commercial transactions thereon, an application user database (7) of authorized users capable of accessing the application server (2), each authorized user in the application user database (7) being uniquely identifiable by means of corresponding login name and password, and a proxy server (10) communicable with the application server (2) and accessible by a plurality of registered users from respective mobile phones (9). The proxy server provides each one of the plurality of registered users with access to the application server (2) from that user's respective mobile phone (9). A proxy database (11) is associated with the proxy server (10), the proxy server (10) containing details of authorized user database (7) who are also registered to access the application (2) server through the proxy server from their respective mobile phones (9).