Pretty good, but a 2 flaws.
The first thing is the lack of the pause button, which I know a lot of people have complained about.
The second thing is the Bowling Mode. It's nigh impossible to get 1500 points (my personal record while writing this is 1490; And that's happened TWICE!)
Also, unlike popular belief, it IS possible to mute out the sound and/or music. In the upper right corner of the screen, there's 3 buttons. Press those to mute/start sound or music as well as toggle quality.
Other than those things, I think it's a pretty good game but the biggest flaw, as I personally think, is the lack of the pause button. More often than not, I have to pray that the enemies will stop showing up if I have to leave for the bathroom or something.