It doesn't support every unicode character yet, but it's getting there. For example, it recognized the Kannada character ttha (ಠ), but it doesn't know the poop (💩) character.
It does! I got it as one of the suggestions while trying to make it recognize the snowman (my go-to character when I stumble on one of these tools).
Did you ever get it to recognize the snowman? That's my go-to also. I've tried two snowballs, three snowballs, with and without arms, with and without stars, with and without hat... and all I keep getting is tongue. I am pretty bad at drawing though.