Have you ever squeezed a tennis ball and said to yourself, "Man, I'd love to use this thing as a mouse, if only it was covered in gel and had a scroll wheel?" No? There's a good reason for that.
It's $35 at Amazon.
I want you to do so something for me. Take your arm place it on your desk, next to your mouse, in a natural pose. (Or trackpad, whichever.) Note the position of your hand, the amount of arch in it. Your current mouse very probably fits in there, give or take. The Jellfin doesn't.
You've either gotta arch your hand or your fingers to hold it, like you're about to throw a curve ball. And, uh, it's not very comfortable after a couple of minutes. I tried relaxing my hand more, different positions, different grips, different mousing surfaces. It's like a hellish, glorified Taiwanese OEM spin on the most miserable mouse Apple ever produced, the hockey puck.
The physical feedback from the buttons kind of sucks, too, because of the squishy gel coating that surrounds the orb (which otherwise, I like a whole lot, actually). Oh, and the whole thing feels cheap. The one decent piece of design work is that the scroll wheel is inverted—that is, you physically scroll upward, toward yourself, to scroll down on screen, which feels more natural with the way you hold Jelfin.
There's no reason to ditch your mouse to get this one. Buy a more ergonomic mouse if you need one. Buy a stress ball if you need one of those. But don't buy this thing.