A patent filing from 2012 may have revealed what future technology Apple is currently working on.

The U.S. Patent and Trademark Office has awarded Apple a patent for an "intelligent stylus," which sports interchangeable nibs, built-in sensors, advanced microprocessors, fingerprint recognition, an eraser and a more innovative algorithm, among others.

According to Apple's U.S. Patent No. 9,329,703, the proposed device is somewhat similar to the current Apple Pencil, but it's a smarter version of the popular iPad drawing accessory. The existing Apple Pencil already has built-in sensors that enable the device to read hand gestures, measure proximity and sense variations in pressure as its conductive nib makes contact on the iPad's screen.

The next-gen of Apple Pencil, however, will feature additional hardware, including interchangeable nibs with individual sensors. Each tip will include a variety of brushes, pencil and felt-tip pen that will allow users to create different paint strokes using the stylus. It should give users a similar experience to holding an ordinary drawing tool.

Additionally, a sensor attached at the opposite, non-writing end of the stylus, will work as an eraser tool when it makes contact with the tablet's display screen. Apple has a list of other proposed nib innovations, including force-sensing bristle brush, flashlight and motion-tracking camera.

Another interesting feature described in the patent is the fingerprint recognition using Touch ID. Though it's a little out of the ordinary to tie this feature on a stylus device, it can still serve as an effective security measure. The device will deny any user whose fingerprint is not recognized.

The Apple Pencil is still a relatively new technology, having released in November 2015. It has been received positively by consumers for its classic design and usability, but releasing a follow-up device may be too early at this point. However, it would not be surprising if Apple releases the interchangeable tip feature sooner, since it could be a great addition to the current product.

Like any other patents, there is no guarantee that the features mentioned in the document would all materialize into an actual device. However, it still creates enough buzz to excite Apple fans, who eagerly anticipate the latest Apple products that will enter the market.