Stream from my Android over Wifi to my amp I have an HTC One and I would like to stream music over wifi via any player app (PowerAmp, Google Play, etc..) to a stereo amp. 

I looked into Nexus Q, Sonos and more. Which one will actually support any player app in my device, letting me stream the music smoothly straight forward to my amp?
I am looking for the same solution and the only thing I have come up with is the Sonus Connect.  It sells for around $300.  Have not tried it yet, but seems to fit what you are looking for.  Basically you would transmit audio from your phone to the sonus connect.  The sonus connect would be wired to the amp and the amp to the speakers.