That's a neat concept you've got there! It's really hard to get used to the gameplay, mostly because a) I'll reflexively move both cars (or just the wrong one), or b) I'll move a car too soon and it will hit something next to it. That's not a criticism, just a comment.
For whatever reason, the full screen button in the arcade wouldn't work on my phone. That's not your fault, but perhaps you may want to consider adding your own fullscreen button?
Also, are there keyboard controls for this? Since the controls are so simple, it should be pretty easy to support both touchscreens and keyboards (unless you've already done so and I haven't noticed).
Next, there are some spelling and grammatical errors on the instructions page (like "vehicals"). Might want to take another look at that.
Lastly, the gameplay seems rather repetitive, with nothing but stationary things to hit and stationary cars to avoid (unless I just never got far enough to see anything else). I think it would be cool to add some random events, powerups, moving obstacles, or whatever else just to keep it interesting.
Anyway, it's a fun game to pick up and play for a couple of minutes. Nice job!