> The reason is because based on the research I did, I saw that trackball had a steeper learning curve and less usage preference overall, and even though vertical mice also have a learning curve, it seems to be lower. Plus, I believe it's easier to use optical tracking for other actions such as gaming.

Thanks. Those are good points. It's fun for me to see people not use to a trackball attempt to use mine. It definitely took me some time to find it 'natural' with FPS games. It makes sense for you to target a larger audience of potential buyers.

> How do you like your trackball? Do you get any pain on your fingers or hand after using it for a while? Maybe a product to explore as a second iteration if the first version goes well :D

I love it overall. My thumb joint does get a little sore/tired after long use (nothing compared to wrist pain). So I have considered switching to one that relies on your fingers instead. Also it works on any surface so it's great if you want a 'full' mouse with a mobile device.

I would definitely recommend exploring it as an option down the road, though I'm guessing it's still a relatively niche market.

Here's wishing you success finishing and launching your product!