In one example, a device for retrieving media data includes a memory configured to store media data, and one or more processors implemented in circuitry and configured to retrieve a file including the media data, web content formatted according to hypertext markup language (HTML), and data indicating how to synchronize the web content with the media data, and present the media data and the web content, wherein to present the media data and the web content, the one or more processors are configured to synchronize presentation of the web content with presentation of the media data according to the data indicating how to synchronize the web content with the media data.