Abstract: A portable computing device (PCD) can be connected to multiple accessories concurrently in a daisy chain topology. with the PCD at a “front” end of the chain. At least one intermediary accessory (or relay) provides one port for connection to the PCD and another port for connection to another accessory, which can also be a relay. Each connected accessory can interact with the PCD to invoke functionality, receive or deliver content, etc. Concurrently, each relay accessory can also act as a relay for other accessories in the chain, directing signals from a downstream accessory toward the PCD and directing signals received from upstream toward a downstream accessory, thereby allowing downstream accessories to interact with the PCD. The presence of upstream intermediaries can be transparent to a downstream accessory.

Abstract: A camera capable of capturing still images and video and included in a portable media device can be controlled remotely using an accessory. The accessory can register with the PMD to automatically receive notifications whenever there is a change in the camera state. The camera states can include mode, operation status, and configuration settings. The accessory can send instructions to a camera application that interfaces with the camera to control the camera. The accessory can remotely activate the camera, change camera mode, and send instructions to operate the camera. The accessory and the PMD can concurrently control the camera. The PMD can send the captured still images and recorded video to the accessory for preview and receive instructions from the accessory on disposition of the still images and the video.

Abstract: Track-identifying information can be collected from a broadcast using a portable media device capable of receiving broadcast content in combination with an accessory capable of communicating user input to the portable media player. In some embodiments, the portable media player can detect the presence of track-identifying metadata (a “tag”) within a received broadcast and can alert the accessory when a tag is available for a currently-playing track. If the accessory instructs the portable media player to store the tag, the portable media player can do so and can alert the accessory when a tag for a track has been stored. In some embodiments, the accessory can also remotely control other broadcast-receiving functions of the portable media device, such as entering or exiting a broadcast-receiving mode of operation.

Abstract: Embodiments disclosed herein provide for capability identification for accessories coupled with a mobile computing device. During capability identification an accessory can request capability information from a mobile computing device. In some embodiments, the accessory can specifically request capability information associated with a specific lingo. In response, the mobile computing device can respond with a message that indicates the capabilities of the mobile computing device that are supported. In some embodiments, the capabilities can be those capabilities associated with the specified lingo. In some embodiments, if the mobile computing device does not support a lingo, then the mobile computing device can respond to the request from the accessory with a negative acknowledgement.

Abstract: A media player can have advanced-playlist creation capabilities such as the ability to automatically generate a playlist around a “seed” song selected by a user. In some embodiments, the accessory can determine whether the media player can use a particular song as a seed song for an advanced playlist and can so inform the user. The user can then operate the accessory's user interface to create an advanced playlist based on a particular song, rather than having to interact directly with the media player.

Abstract: Message notifications to an accessory from a mobile communication device are provided according to some embodiments of the invention. When a message such as a text message, email, and/or voicemail is received at a mobile communication device, the mobile communication device can notify an attached accessory that a message has been received. In response, the accessory can request the full message, media associated with the message, an attachment to the message, and/or an audio/video stream of the message for presentation to a user.