How many levels are there in Grindstone?
I can already see 120, and there seem to be more.
This is Grindstone on Apple Arcade.
The last sentence on the two-paragraph page you linked reads:
150 levels of intense puzzle-battling madness!
Grindstone originally had 150 levels, but free updates have increased this to 230 levels as of July 2020. A daily challenge mode was also added.