You're probably not going to be able to compete with Google Drive integration, but if someone put together a well designed integration of inbox, calendar, and contacts with an API, they would do well.
You're probably not going to be able to compete with Google Drive integration, but if someone put together a well designed integration of inbox, calendar, and contacts with an API, they would do well.
I've been using Apple's Server.app (Formerly OS X Server) for quite some time now at my home. Its definitely a bit of work to maintain, specifically on the CalDAV and CardDAV integration. But failure is something I would hardly attribute to the setup. It's certainly not any worse to use than configuring and maintaining Postfix/Dovecot/Roundcube and CalendarServer individually.
In what way would you suggest Apple's Server.app has failed (outside of the obvious hardware compatibility)?
The web is shitty for serious productivity apps from experience.
Regarding open source, use openoffice instead.
Alternatively use Windows' offline files feature when you are away from the fileserver.
Managing a file server, even if it's just a static workstation on a windows network is easy from security to backup - it's all guided configuration.
Seriously - everything that google apps does can be done on offline MS office and a cheap hosted exhange account.