Apple has applied for a patent with the U.S Patent and Trademark Office (via AppleInsider) on methods for using hyperlinks embedded into audio streams that could offer content creators the capability to link to other forms of media or control a device altogether. The main concept of the patent is outlined in the abstract of the filing, and explains how audio hyperlinks could be used to allow listeners to access such content within audio:
Hyperlinks within an audio stream provide a way for a listener to access linked resources. An audio hyperlink encoded in an audio stream indicates the presence of an audio hyperlink in the audio stream, as well as providing information for traversing the hyperlink to the linked resource. The hyperlink may be conditionally traversed upon a user interaction or automatically upon detection in the audio stream, possibly pausing the audio stream containing the hyperlink during the traversal of the hyperlink and resuming the audio stream if the audio stream is returned to from the linked material. The linked material may be other audio content, but may also be any other type of desired content that may be accessible by the system processing the audio stream.
In the patent application, Apple gives an example of a podcast which could link to other podcasts, websites, or other media, and Apple describes how software could either automatically activate audio hyperlinks when detected or offer a user interface to allow users to have control over activation of the links.
While the patent application does not make any references to specific devices, examples and drawings outline how the process could be applied to such mobile devices such as iPhones, iPads, and iPods.