TL;DR - Which program to use for viewing mulitplex jpg and mp4 360x360 photosphere files?
Bublcam provides http://www.bublcam.com/products/bublcam Photosphere Videos and Photos in Multiplex format as raw, and eventually you can download processed Equirectangular.
I would be really interested in ability to view projected (you know, play, look around like on streeview etc.) raw mp4 and jpg files in multiplexed format, i.e. from four cameras.
Example how multiplexed look like: http://techcrunch.com/2013/11/05/bublcam/multiplex_bubl2/