nathan: if all you need to provide is corporate email/contacts/calendar is Exchange ActiveSync enough?
or are you trying to stop people doing stuff with their email once its on the device
or trying to stop malware running on Android from interacting with their email or?
Both. Because these are personal devices as well, we have to be sure how to do that.
ActiveSync is not enough because if we open it for these devices, it requires encryption on the device.
The only way to enforce encryption, is to use a MDM solution.
Also, we needed to have a standardised app for email (not native client), so we use MDM client to push that out.