SonarPen: Battery Free Pressure Sensitive Pen for iPad

Meet the SonarPen: a pressure sensitive smart pen that connects to the audio port on your iPhone or iPad and lets you design on it like a pro. It can be used for  digital painting, sketching, note taking, and everything in between. Thanks to this pen, the screen senses the pressure you exert with your hand.

What’s neat is these pens are much more affordable than other comparable options on the market. The SonarPen still has palm rejection, shortcut button, and pressure sensitivity features found in more expensive smart pens.