Poor choice of lane colors. It hurt my eyes after about 5 minutes, and it was so hard to see the notes if i even dared to look for them in my peripheral view. 3/5 just for that, i love this kind of games, but that's just a huge setback.
"Need a hint? CLICK HERE!" It says, with flashing letters. I look at it and think "oh, cool! Maybe theres a hint for this particular level!" But Nooooo. It has to go and open a new tab!
Hmm.. This is acutaly really good. If you would ever make a sequel or anything, add some kind of upgrading system, yeah, i know there kind of is one, but a more in-depth system. Also got quite boring after the first two levels, the only thing that changed was probably the stream of zombies and starting cash. 4/5