is there a way to use 2 edtrackers at the same time? I am using one for headtracking and want to place a second one on my gamecontroller or on my foot for thruster controll
Yup. They're just game controllers at the end of the day, you can use more than one at a time. Recognising which one might be a bit of a challenge, depending on the game you're trying to map them in
Only minor issue is the GUI (depending on whether you're talking DIY or Pro). Easiest thing is to configure them individually one at a time (ie. only one plugged in at a time), when you're happy you can then plug two in. The GUI isn't designed to support two at a time but the DIY GUI uses a COM port so it's actually relatively easier to do with the DIY device, as you can choose the COM port from the drop-down. At the moment, the Pro GUI will just pick the first one it finds... I believe...