Keep your data backed up over wifi on your computer at all time.
I use FolderSync to sync files to my computer via SMB/CIFS. I never tried it on ubuntu as I only use it to build/compile a rom from source so there isn't any space left. But I think there won't be any trouble. I'll try to establish a connection and get back to you if it works.I've my phone connected with USB almost all the time, but I need some scripts\apps for my Ubuntu.
yes this forum required registration for downloading files, I'm primarily reader