Functionally it works nicely. Looks good full-screen on Galaxy Note 10+. Are there any specific things you'd like tested or want feedback on?
I don't play the daily word puzzles that often, though I have. I don't think you have any problem finding an audience in those who play games like this, though, because it's definitely a cool concept and neat game.
I've played about 5 games and some of them I've nailed and some of them I was pretty lost, so I don't think I have enough of a sample to comment on the difficulty, but I think it's working fine for now. I have had a few times where the initial word had me totally lost, and the first move was essentially a guess, but then again I don't have that "word game" brain that many do, hah.
When I first started, I didn't really get the concept of it, though now that I have it figured out, re-reading the tutorial makes perfect sense. That might just be on me. For example, I didn't remember at first that I had to re-tap on the red X to turn it back over, and thought that square was just out of play.
Anyway, best of luck and keep us updated on progress!