USI pens have finally reached the promised land. By the way, USI stands for the Universal Stylus Initiative. The 2.0 specification will now add support for NFC wireless charging. That removes one of the most obnoxious obstacles from a USI wireless pen.
USI pens, which are natively supported on virtually all new Chromebooks as well as some PCs, are boring by design. A USI 1.0 pen is compatible with every other, so that you can swap back and forth as you see fit. But the standard has always had one weakness, which is shared by earlier styluses as well. They've either required a thin AAAA battery or have used an awkward wired USB charging connector to recharge.
USI 2.0 changes all that. Now, the standard supports UFC charging, so that pens will be able to charge while resting on a Chromebook's NFC pad (if it has one) or magnetically docked. Of course, that means that your stash of AAAA batteries has now become largely irrelevant.
Another major change is the upgrade to the color pallet. A USI 1.0 pen only supported a measly 256 colors, making it suitable for some basic drawing but not much more. Now, the USI 2.0 standard supports over 16 million colors, making a USI 2.0 pen much more suitable for artistic inking, drawing, and illustrating.
The USI 2.0 specification also supports in-cell display panels, where the touch panel is beneath the glass substrate rather than on top of it. The Universal Stylus Initiative, which controls the USI standard, also said that these pens will have increased tilt support as well. USI 2.0 launches six years after the original specification, authored in 2016.