Does anyone have a good guide or experience moving from Google apps to a completely self-hosted open-source solution for email, contact-management and calendering?
Can you make all of this (more or less) seamlessly integrate with mobile-platforms like Android?
iOS is obviously not a trust-worthy solution, and Android, while owned by Google is at least open-source. If you go super-paranoid you can always builds not integrating with Google's services in any way.