Android USB audio resource lists:
"A list of standard USB DAC reportedly interworking with the Android-powered smartphone Samung Galaxy S4:
stock Samsung Galaxy S4 > digital USB audio out >> USB OTG cable (ID pin grounded) >> standard USB DAC>> amp >> headphones
. iBasso D-Zero (USB DAC/amp):
Right now I'm bidding on a D-Zero on ebay. I'm from Europe and it is surprisingly hard get my hands on a D-Zero.
Does anyone know of a Europe based store that sells them?