OK so this might be tough. Back in the summer of 1981 I had my first exposure to the Apple II. My neighbours had one and a few games for it. I remember Brickout or something similar. The other game was a very simple one where your "ship" or whatever it was was in the center of the screen. You used the paddle to shoot and you could only shoot in 4 directions. Aliens (or "something") came at you from the 4 different directions and you had to shoot them before they got to you.
I've attached a really poor screenshot of the idea - it's not exact, by any means, but just demonstrates the concept of what I'm referring to.
It's quite possible it was not commercial, and written in BASIC. It was included with the computer from the dealer.
Anybody remember anything like this? I'm working on a project and the origin / name of this game would really help