I really like this game, and find myself coming back to it when I'm looking for something to kill some time. I actually really like the sparse feel to it though I can understand other reviewers noting the lack of sound and other "gamey" features.
My only real qualm with the game is the fact that I don't have the option to skip the tutorial level. Not a huge issue overall, but something you might consider if you're going to develop this series further (and I hope you do!)
Cheers!