Hmmmm...
This game is not that bad, but there are clear room for improvement.
The grafics were ok. I think it would improve the game if after a wile there came some new stuff after a wile like some stronger zombies or something. Also that you had to click on the battery to "reload" was a problem. It was also repetitive and after a wile it got boring. Finaly I think that there should have been possible to pause and upgrade your weapon.
Whit a little work it migt grow to a 9 or a 10.