Features of the HydraBus board:

Features of HydraBus/HydraNFC open source embedded native firmware (hydrafw):

Links:
For more info on firmware see github: https://github.com/bvernoux/hydrafw
For latest official release of hydrafw (pre-built version) see github: https://github.com/bvernoux/hydrafw/releases
For more info on hardware for HydraBus see github: https://github.com/bvernoux/hydrabus