Here is an example on how it parses my terrible handwriting: https://websites.instantwebsite.app/wPhkwSStQvStUrzPC9jW5Kw/...
(no, I'm not a doctor)
According to the licenses on the device, the handwriting is "partially powered by MyScript" which seems to be this service: https://www.myscript.com/
https://handwritingsuccess.com/
Edit: looks like they have released an iPad app since I last tried it! I’ll also add that when I first did it I found doing the worksheets pretty relaxing as a wind down exercise, in the same way that mindlessly playing puzzle games on a phone would be, but with much more benefit.
Jokes aside, practice PDFs for improving my handwriting does sound interesting, thank you for taking the time to share it.
For me, at least some of it is that the pen is more pen-like ("hard" rather than with a tip that depresses), and the sampling rate is much higher than e.g. a Surface. I have a Surface device and I absolutely can't stand writing on it - I have to write huge and slowly and lift a couple mm, or it screws up all over the place. ipads are dramatically better, but they still sample slower AFAICT, and close many of my "e"s into "c"s and similar loss-of-detail.