1. An automated method for determining a user's likely exposure to media content being output by a media device based on user interactions with a mobile device that is monitoring the media content being outputted by the media device, the mobile device including (i) a media content sensor, (ii) a media content monitoring application configured to interact with a search engine that performs automated content recognition, and (iii) an interaction detector component, the method comprising: (a) automatically detecting media content which is playing on the media device in proximity of the mobile device using the media content sensor and the media content monitoring application by: (i) creating segment representations of the media content and electronically communicating the segment representations to the search engine, and (ii) the search engine comparing the segment representations to known segment representations of media content to detect the media content; (b) automatically detecting user interactions with the mobile device using the interaction detector component; (c) storing in a memory: (i) information identifying the detected media content, (ii) timestamps of the detected media content, and (iii) timestamps of the user interactions; and (d) recording a user media impression for detected media content only when the timestamp of the detected media content is within a predetermined time value of the timestamp of a user interaction, the media impression indicating that the user was likely exposed to the media content.