Apple doesn't offer a stylus for the iPad and has never promoted their use for either the iPad or iPhone though plenty of third party companies offer the accessory for artists and others.
But based on a recent patent filing with the US Patent and Trademark Office, it's clear that Apple's R&D labs have been tinkering with new ideas for a stylus.
The "Input Device Having Extendable Nib" patent filing sees the nib of the stylus as the key to its power. The nib would be able to extend, thereby offering different capabilities based on its length.
At its smallest length, the nib would have a limited number of areas that it could interact with a tablet. But extending the nib would increase the number of multitouch points, giving it the ability to create strokes of different colors, widths, and formats.Source article