I haven't tried it but it has a couple foot sensors that are used to control it. Probably more preferable if there was some way to link it into the nervous system without surgery, but lacking that it's going to piggyback on some other fine motor control.
It's apparently like driving a car or riding a bike or swinging a hammer, there's a small learning curve but with a little practice it's overcome pretty quickly and feels like a natural extension of yourself. But yeah given a preference I'd probably want to try tying it to wrist or hand movements for practicality.
Someone else who knows how to finger count in base-12 and binary!
I think the binary one I learned as a joke, show someone they are number four.
The base-12 was an explanation for how the ancient Sumerians finger counted, using the other hand's fingers for groups of 12, leading to base 60 (5×12).
I have the same problem with binary counting practically though, and using a modified Sumerian system (both hands to 12) gets you to 144, which is plenty for anything where finger counting is actually useful.
One other thing, I use the finger bones rather than the knuckles, little easier but same idea.
If only we could combine the two and get to 2^12... Sadly, this would require 12 thumbs.
Ooh, actually you can get to 2^8 without worrying about those pesky tendon issues by putting your fingertips against your thumb instead of trying to extend your fingers... Hmmm... Maybe we can even go to 2^10 this way by incorporating knuckles. Might lose some time today figuring out more hand counting systems. I wonder if anything higher than 2^10 is possible...
Some might say it's giving finger counting too much thought, others might say it's a tangent too serious for dad jokes, I say… the efficiency gains seem to come from a change in technique for how a count is stored.
Base-10 finger counting technique just accumulates, the number of fingers held up is the count.
Base-12 uses a pointer (your thumb) to point to a value (a knuckles or finger segment).
Base-2 uses a finger up or down to show a place value as one or zero.
You could tattoo numbers on your forearm so all five fingers from your other hand could point to a value for up to five more places to point.
(Western) base-10 needs two hands. Base-12 is one-handed. (There's a base-10 system used in China that's one-handed, mind. Or, rather, it's one-handed until you reach 10.)
Also some maths operations can be done fairly easily (like division) with the base-12 finger-counting system.
Base 10 on your hands is really base 1. Every finger is either 0 or 1 and we just count them! Base 12 we do have 12 positions each representing a digit, and two potential digits from our hands.
Binary is so much more efficient because you have 10 digits, just like in base 1, but you use them more efficiently.
The next logical step is trinary, if we can incorporate enough fingers it would go higher than binary. Wikipedia suggests three positions of your fingers - up, down, and somewhere in between, or folded - but I'd be surprised if anyone can realistically do that with all their fingers. However, using four fingers on each hand and pointing them at different knuckles/the tip of your thumb gets you 8 digits of base 4 (including not pointing at the thumb at all as 0).... And actually doesn't tangle your fingers up too bad.
There are a great number of ways you can count on fingers. You can easily support base 4, base 5, base 8, base 10, base 12, base 16, base 19, and even higher (144, say) with finger counting. There's nothing particularly "natural" about 10.
Theoretically, but most bases above 10 require using other bases as intermediate steps. Base 10 was used because it was the largest number you could easily count to without relying on a number system already existing.
Base 10 was used because people in one influential area counted the tips of their fingers. But there are recorded (and in some cases still living!) finger counting systems where they count using the gaps between the fingers (giving us base 4 or base 8 depending on how many hands are used), using the thumb and the finger segments (base 12), the same as base 12 plus the finger roots (base 16), etc.
There is literally nothing "natural" about base 10. Indeed it's not even a particularly useful system; bases 12 and 16 are far more useful given how you can do divide them in many more ways than base 10. It just happened to be the one that was used by the cultures that became most influential.