Nintendo has filed a patent application for a stylus which connects to the Switch’s Joy-Con.
Proposed designs popped up online this week (thanks, Siliconera) and show a rejigged Joy-Con strap with a pen-like nubbin on top.
When attached to a Joy-Con, the device would act as a stylus for the Switch in handheld mode. Examples for its use shown in the proposed patent include as a simple touchscreen input, or to allow more detailed drawing. You can imagine it being handy for things like Dr Kawashima’s Brain Training’s touchscreen puzzles, or level design in Super Mario Maker 2.