A mobile telephone obtains (or is supplied) advertising content from a remote server and locally stores that advertising content. The advertising content is then automatically shown in association with a running, in use (e.g. in foreground) application that generates a screen that an end-user interacts with (‘an end-user application’). The content is shown ‘automatically’ in the sense that the advertising content is displayed without the end-user explicitly requesting any specific item of content, (although he may opt-in to the general approach of having advertising content displayed on his mobile telephone). The telephone itself determines which adverts etc. it should display, depending on which application is currently being used (i.e. is currently displayed on screen).