The iGun is a projectile-based weapon produced by Apple Inc. after Steve Jobs totally fell off his rocker. He ordered it to be made so he could shoot his rocker. After he destroyed his rocker, he decided to destroy some other stuff too. This maniacal rampage of destruction is commonly believed to have played a large role in Job's death.
The iGun functions through a battery-operated heating system. The battery gives off a big burst of energy, charging the ionizers. The ionizers then project heated oxygen forward as a green bolt of plasma. This plasma moves at about ten MPH (or about 16 KPH for you non-UnAmerican folk). This weapon has an efficiency rating of 4%, making it the most effective device Apple Inc. has ever developed.
The idea of the iGun was later stolen to be used in Call of Ducky, though there were some minor changes. One of these changes, for example, was the fact that the gun was able to hit a moving target.