Very simple tic tac toe, it's a game that a lot of people know and play and it would be so much more amazing if you put your own personality on it would be the feedback I'd give.
maybe different colors/styles?
some nice music/sfx?
possibly more modes (like a tic tac toe board with 4x4 instead of 3x3)
it's functionality is there and it has it's playability, but originality isn't, there's 100's (thousands) of tic tac toe games out there, as a fellow artist myself - set yourself apart and make a "better" tic tac toe by adding more features and making your game better than the rest per say.
Only giving a 3 star because of originality issues, you can do it!!