I use the Nine mail/calendar app[1] to keep all that contained. It integrates nicely with the native Android apps but keeps all of the security and control options within Nine itself. It looks like they are also beta testing an iOS app but I have no experience with that version of it.
For example, if the mail account security settings require a screen lock code, Nine will require a code to access the app but this won't affect the actual phone's unlock screen.
Similarly if a data wipe request is sent from the server it will only affect Nine.