Hi Athanasios,
> i wonder if I can redirect audio from my android mobile phone to a jack
> server (preferably) or pulse audio server (not so preferably) through wifi,
> in much the same way this can be done through bluetooth.
Linux-Audio and pulse is not a good partnership and for using jack you
have to build yourself the Android and for sure it has to be rooted.
Not everyone can do this or wants to root his phone. An Android 4.4.2
device is needed. The code and instruction you can find on GitHub.