For some crazy reason, my Trackpad stopped working in Safari. It would not go back pages when doing the three finger swipe. So what I wanted to find out is if the Magic Trackpad runs off Bluetooth. I remember when I first got the MBP, that my Bluetooth was turned off. After having the issue I described with the trackpad, that is when I turned it back on and everything was working properly. I'm cautious to keep it running all the time because like on the iPhone, it drains the battery.