joker97: on the other hand NZTF ... can i connect S3 or Note 2 to Fiio E17 digitally?

Sadly no, seems to be a problem on the E17 side, since it doesn't seem to play nicely with many non-PC devices at all. Many other USB DACs are working with the S3 and Note 2 though - there is a full list here

For myself I am getting the RSA Intruder USB DAC/amp once they start shipping, and also the Leckterton UHA-6S.MKII to use with mine.