Apple's unique idea for a removable clip that could add tactile buttons to a portable device was revealed on Thursday in a new filing.
The patent application was published on Thursday by the U.S. Patent and Trademark Office under the name "Removable Clip With User Interface." It shows an iPod-like device with a slot on top where a clip could be inserted.
But the clip could offer more than making the device wearable: Apple's concept includes a data connection and accompanying physical buttons that would allow new control methods on the device.
In one variation, the clip is transparent, and the buttons on it correspond with information shown on the device screen below.
In another illustration included with the filing, a transparent clip is not necessary because the accessory does not cover the screen. Instead, the clip and its buttons cover the back side of the device, allowing new input methods while leaving the front display unobstructed.
In the patent application, Apple notes that clips included on existing media players serve only one function: to clip the device to various objects, such as the user's clothing.
"While today's clips provide a valuable function for portable electronic computing devices, they are deficient in that the real estate used by the clips is underutilized, in that the clips are only used to attach electronic devices to other objects," the filing reads.
"Such underutilization is particularly undesirable as technology continues to miniaturize, since even the smallest amount of real estate used by a device is often considered burdensome by a consumer."
The application, published on Thursday by the USPTO, was first filed by Apple in July of 2011. The proposed invention is credited to Teodor Dabov and Fletcher R. Rothkopf.