Google Cardboard for BIMx has a touch sensitive button on top that activates the control button on the BIMx screen.
I am not sure if this is true of all Google Cardboard models or if it is just the ones put out by Graphisoft.
You will find that the plastic VR sets don't have this button so don't really work with BIMx - at least that is my experience.
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It looks like the one gpowless purchased has the button, although it is currently unavailable. Barry is right though, about the button. I just bought a very nice one on eBay, unaware of the need for a button. It was only $8.49 with free shipping. It is almost useless for BIMx unless I can drill a hole in it for my thumb to have access to the screen.
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