S'alright, thanks for the suggestions anyway.
My interest in this device is that it might provide a compact solution to my main goal, which is to maximise my enjoyment of Spotify via my Android phone.
I'm not really interested in i-devices, even though I covet the iphone4/vamp combo (the form factor at least, I've never heard one, but I love the cable-free & compact nature of the device).
I've read the reviews for the A200p ( and AK variant ), and can't say that I'm overly enthused by them, but it is small, and has it's own battery.
The most useful thing for me would be a simple list of usb dac/amps reported to work with Android.
Once I'd found any that match the form factor/features I'd like, I could then use Danba's amazing work to check compatibility with any phones I might consider/already have.
Is there such a thing as a simple list of portable USB DAC/AMP's where I can start?
I know of a few devices, but I bet there are many which I'm ignorant of.
If V Moda ( or FiiO/iBasso etc for that matter )decide to make a V-amp style case/dac-amp to fit the Sony Xperia z1 compact I will be launching money at them so hard they'll need armour.