The best so far

I have installed this app on both my iPhone 4 and my iPad mini. on the iPhone it works perfectly up to 24 bits /96 kHz source, with higher sampling rates (192 kHz) the playback becomes unstable. This is obviously due to the hardware limits of this device.
On the iPad mini, no issue to playback the highest sampling rates.
The network streaming is powerful, works very well with my FREEBOX revolution box, the files being stored on the hard drive.
Plenty of audio tuning possibilities. The EQ is excellent.
I have not tested Neutron with an external DAC so far, unfortunately, so no idea how thiss application behaves with an external device.
Its the most powerful app I have found so far for playing hires audio files, in second position I would recommend Onkyos HD player

Glodiusse about Neutron Music Player, v1.79.4