SonarPen is a $30 iPad stylus that connects to the headphone jack

An affordable alternative to the Apple Pencil

MINI-STYLUS DUST PLUG 3.5mm headphone jack for iPhone 4s 5c 6 plus Galaxy s6+ s7

SonarPen Is A Smart Stylus That Works With Any iPad - iOS Hacker

SonarPen, a pen for any device with an audio jack, iPad, iPhone, android and chromebooks

Connects SonarPen to your device's USB type C port., Required for SonarPen to works on Windows computer.

SonarPen USB type-C to 3.5mm headphone jack adapter

Colors Live Review (Switch / Switch eShop)

Can I Use A Phone Stylus For A Switch - Snow Lizard Products

SonarPen is a $30 iPad stylus that connects to the headphone jack

Colors Live is Now Available for Pre-order - Includes Pressure Sensing Pen : r/NintendoSwitch

SonarPen USB Type-C to 3.5mm Headphone Jack Adapter : Electronics

SonarPen users, Hi guy! I have just received my Sonar Pen yesterday, so it took a whole month and a few days to arrive here in the Philippines

Smart Stylus for Android Chromebook Drawing Stylus Pen for iPad & iPhone - SonarPen

SonarPen: A cheap, pressure-sensitive stylus for sketching on older iPads