I'll ask my team about on-site possibilities of communication.
In meanwhile, social network could also help you sending messages as well as emails.
Viber also allow Japanese writings if you have Japanese character on your mobiles (I'm terrible at IT
or any technology, so, sorry if this is a feature of only smart phones...)
Messangers or ooVoo would work just like Skype.
Hope you can figure out some good way to communicate