A US patent filing published today suggests Apple has been researching the prospects of a wireless headset with its own media playback support. The device would operate as a typical wireless headset as a companion for an iPhone or similar device but would play music from storage built into the earphones. It could have basic music controls and a display, but with a microphone it could also use voice commands to play specific content without looking.

The built-in flash memory could also be used in tandem with a host device to save battery life or space on a host device. It could cache some music on the headset and avoid having to stream the signal wirelessly, for example, and record either voice memos or an entire phone conversation without occupying storage on a phone. Apple suggests it could use USB to offload content directly to a computer or else use the headset's wireless, which could involve Bluetooth, RF or even infrared, to sync content wirelessly.

A development of the sort could be monaural, like most Bluetooth headsets for calls, or move to stereo with either a headband or a cord linking to the other earpiece. Mockup drawings show a device near identical to the Apple Bluetooth Headset but are believed only to be illustrating the concept rather than revealing a prototype. One shows a single-piece unit with a built-in screen and a cap that covers a data port, but others present examples of how a stereo version could look.

The invention is credited to John Tang from Apple's Industrial Design Group and was originally filed in April of 2008. It's unclear whether Apple will use the technology; like most patents, the application isn't an indication of intent and doesn't necessarily translate to production hardware. Regardless, its description suggests the possibility either of a more advanced Bluetooth headset for the iPhone and iPod touch or else a fully contained replacement for the iPod shuffle that builds the device into the earphones and may offer additional features.