Does it work? There seem to be screenshots and nuanced wordings that implies it's currently more often configured like a gyro mouse with a touch button...
As a replacement for a desktop user's mouse? No. Could write paragraphs about how it's a special niche, and the device shines in that niche.
I've been in the HCI-enthusiast space due to carpal tunnel for a while now. I actually caused myself to have to have the surgery after going all out with QMK mouse keys, which ended up just moving the problem to a different set of fingers. (So maybe not an expert.)
The part I'm not sure is if they have precise tongue location working, of if they have resorted to the pad as mostly just hot corners. I don't have that much doubt about the concept.
I've been in the HCI-enthusiast space due to carpal tunnel for a while now. I actually caused myself to have to have the surgery after going all out with QMK mouse keys, which ended up just moving the problem to a different set of fingers. (So maybe not an expert.)