Well, to be honest I have still only used it with an iPad and have now by mistake left the PSU on another continent. I will let someone else answer the USB/TRS question with certainty! 
I think, though, that it is manufactured in China. I base this on that I remembered an email with shipping details from Embome during the Kickstarter campaign.
This, if course, is not a 100% fact that is was manufactured there but perhaps pretty close!
All in all, I am very happy with the Erae Touch if you are interested in an opinion about it.
(And if anyone can recommend a good replacement PSU until I get mine back, I would be very happy! )