I'm actually not much help here I'm afraid. The only mobile VR we really do right now is on the Oculus Go. We share our images (unlisted) with clients at
https://kuula.co/ from our video shoots and such, just because it posts nicely to Twitter and other places that aren't 360 friendly.
That said, although a hands free 360 image viewer would be really easy to make (add a gaze to look spot to advance the images) we just haven't needed one internally on our side, so I'm not sure what a good one would be...