I will add though that not every DAC will work with every Android device, not even all newer Android devices. For example, the E17 works with the S4, but it has been reported that the E7 does not. It's also been reported that the E7 works with the older S3, but the E17 does not. Same with the newer HTC, Sony, and LG Android phones, not every current Android is compatible with every DAC. So it seems to be a bit hit and miss unfortunately.... See, I'm not a total Android fanboy, I'm just calling it as it is.
James Fiio said in the Fiio E18 thread that apparently E17 works on 4.2.x (therefore Galaxy S4), and E07K on 4.1.x (SIII, Note II, and others). Basically, don't update if you have the second one...
In my case with the E07K, it works in my Note, but not in my Nexus 10 (4.2.1), so it follows the rule pretty well. It might be DAC related.
I'm curious to see what happens with 4.3.
Edited by Ashade - 7/28/13 at 11:32pm