There’s a long history of very good reasons for using an external keyboard instead of your MacBook’s, but it does put the laptop’s very useful trackpad out of reach. Instead of spending $149 on Apple’s standalone Magic Trackpad, Taliyah Huang designed and built a custom split keyboard with its own mouse and trackpad functionality built right in.
There are already many external keyboard options with integrated cursor controls that let you skip the mouse altogether, but the solutions are usually either a trackball, an incredibly tiny touchpad, or the even tinier nubs you’ll find on laptops from Lenovo and Dell, which all tend to sacrifice accuracy and usability for being small and unobtrusive.
In their quest for a better all-in-one keyboard solution, Huang took an entirely different approach. The right side of their split Mouseky keyboard also doubles as a mouse, letting them control the on-screen cursor by simply dragging the whole thing around without ever having to take their hand off the keys. Inside the keyboard’s right section are the guts of an actual optical mouse, but to eliminate accidental cursor movements, it’s only active while the right section’s CAPS LOCK button is pressed.
The right section of the keyboard also supports scrolling in four directions, zooming, switching between multiple macOS desktops, and other MacBook trackpad functionality through various keyboard shortcuts, and the whole thing is wireless, although that sounds like it also might be its downfall.
According to gizmodo.com