According to some fairly shady “research”, these toys improve concentration, and that may be correct for a limited number of kids with specific learning issues, but, yeah.
Trolling around the interwebs, I noticed a post on an obscure Chinese (I think?) forum that offered a photo diagram of a “finger gyro” (a much better name) folded from an equilateral triangle, so I knew I was destined to “get down and jiggly with the kids” and fold one.
This is a clever fold, managing colour change and layers to re-distribute weight around a hex-twisted spindle, and it spins – no, truly it does.
The designer is Mike Luo