A media system comprising a broadcast system, a telecommunication system, a content processing system, and a user terminal. While a media stream is broadcast, a group of content items associated with the media stream are generated. The content items are presented in the user terminal in a first mode, wherein a presentation element corresponding to a content item is changed to another presentation element according to the timing information of the content item, or in a second mode wherein a presentation element is changed to another presentation element in response to a user action. Transition from the second mode is allowed only by authorization according to a pre-defined procedure. The interactive operations are thus controlled by the user and thus not overridden by content timed or pushed to the user terminal for display.