Apple Pencil can be utilized to provide input by contacting a touch sensitive surface that, in response to detecting a touch event, generates a signal that can be processed and utilized by other components of the Pencil. More specifically, Apple Pencil today offers Double-Tap to change between artistic tools. Apple's second-generation Apple Pencil debuted in November 2018.

With Apple Pencil 2 going on 4 years without an update, you have to wonder if there could be a third generation Apple Pencil arriving this year along with the next-gen iPad Pro.  

A new patent application from Apple published last week by the U.S. Patent Office describes possible new sensors could be implemented in an Apple Pencil that support user squeezes, multi-taps and/or sliding gestures.  Apple notes in patent point #0048:

"For example, as a user applies a finger at the housing, the stylus can detect the resulting capacitance that is induced in the touch input sensor. The user can subsequently lift the finger, and the stylus can detect the resulting capacitance or change in capacitance that is induced in the touch input sensor. The user can subsequently return the finger to the grip region, and the stylus can detect the resulting capacitance or change in capacitance that is induced in the touch input sensor. The sequence of inputs within a span of time can be interpreted by the stylus as a user's tap gesture. Multiple touch input sensing elements of the touch input sensor along the stylus can be used in concert to detect sliding gestures."  

Apple further notes that the Apple Pencil (stylus) can allow the user to interface across a touch panel in a pattern that the device translates into an input command. Apple Pencil can include one or more sensors to provide additional input capabilities. For example, Apple Pencil can include one or more sensors to detect a squeezing or compressive force against the body of the Pencil. The sensors can be capacitance sensors, strain gauges, force resistive sensors, magnetic/inductive sensors, pneumatic sensors, piezo sensors, and/or optical sensors.

Below is list of possible force sensor types that Apple is considering to use in a future Apple Pencil. The types include strain gauges; force-sensitive resistors; inductive sensors; pneumatic sensors and piezo sensors.  

For details of the invention, review Apple's patent application 20220100290.  

Considering that this is a patent application, the timing of new sensors and/or features for Apple Pencil is unknown at this time.