8. A computer system, comprising: one or more processors; and memory storing one or more programs for execution by the one or processors, wherein the one or more programs comprising instructions for: obtaining a video stream configured to be displayed on a first display device to a user of the computing device, the video stream including closed captions; identifying one or more symbols or words included in the closed captions; determining a media content category for the video stream in accordance with the one or more symbols or words; determining and obtaining a set of instructions from a server, wherein the set of instructions includes instructions to invoke and display a media content application relating to at least one symbol or word in the one or more symbols or words in accordance with the determined media content category; and in response to obtaining the set of instructions, without user intervention, causing the media content application to be invoked and displayed on a second display device to the user of the computing device concurrently with displaying of the video stream on the first display device; wherein the one or more symbols or words include information identifying a person, and in accordance with a determination that the person identified is associated with a predefined importance value, obtaining the set of instructions in accordance with the predefined importance value associated with the identified person.
10. The system of claim 8 , wherein the one or more symbols or words include at least one sentence extracted from the closed captions.