I'm using an app on a MDM device (MobileIron) which uses MFMailComposeViewController. Unfortunateley, the contact picker does not have access to the address books, esp. the global address book (AD). The picker has only access to the contacts provided by Siri from the indexed mail app.
According to my collegues managing the MDM, the app should have access to the addressbook, as the app itself has the status "managed". Therefore: Is there a missing configuration or a bug?