Organizations utilizing the Outlook app on iOS and Android may desire granular control of app behavior such as only allowing certain contact fields to be sync'd with the native contacts app on iOS. Fortunately, Outlook settings are available to further control the Outlook app on iOS and Android.
I've worked with organizations who have strict data protection and GDPR requirements and utilizing Intune we were able to protect data from leaking from users' corporate email to unmanaged apps and storage while allowing limited contact attributes sync'd to the local contacts app so caller ID will show for callers residing in contacts. Some of the restrictions are enforced by the platform (i.e. iOS/Android) while other restrictions are controlled at the app and device layer by Intune.
To learn more about app config with Outlook please visit: https://docs.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/outlook-for-ios-and-android/outlook-for-ios-and-android-configuration-with-microsoft-intune#configure-contact-field-sync-to-native-contacts-for-outlook-for-ios-and-android
As you walk through the settings make note of the "Device Enrollment Type" for each configuration setting, e.g. "Managed devices", "Managed apps". The device enrollment type corresponds to the Intune "Device enrollment type" setting when adding a configuration policy (see screenshot below). It's important to understand the differences as there are different settings for different types of profiles and if settings are used for an unsupported profile type, they simply will not deploy to the app. In addition to the contacts settings, there are also account configuration, wearable, and iOS notification settings that can be configured as well.
Let get started
The following example demonstrates syncing only certain contact fields to the local contacts app so the end user will see the caller ID for a contacts for phone numbers when calls are received.
Navigate to the Intune admin portal and select "Client Apps > App configuration policies > Add"
Give the configuration policy a name and select "Managed apps" as the Device enrollment type as I'm pushing this policy via an App Protection Policy.
Select "Associated app" and select Outlook for the platform(s) you're interested in configuring Outlook for. For "Managed Apps" I recommend using a single policy for iOS and Android to maintain consistency across platforms.
Add configuration settings to configure the app configuration settings for contacts in Outlook as shown below. These are key/value pairs and are documented here: https://docs.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/outlook-for-ios-and-android/outlook-for-ios-and-android-configuration-with-microsoft-intune#configure-contact-field-sync-to-native-contacts-for-outlook-for-ios-and-android
I'm only allowing first name, last name, and mobile phone number. If other phone fields are required such as home, office, other, you may want to allow those as well. Note: these fields match up to the existing fields in Outlook contacts and the native contacts app.
Assign the policy to a group of users:
Syncing contacts to the native contacts app
For contacts to show up in the native contacts app, users need to manually select "Save Contacts" in Outlook settings to sync contacts to their device.
Note: if you don't see "Save Contacts" an Intune App Protection Policy may be blocking contacts sync. To check APP settings install and open the Edge browser and type in: about:intunehelp in the search box and view Intune app status for Outlook. If block contact sync is enabled, it will be set to "1" disabled will be set to "0". Also, the "Save Contacts" setting cannot be set by policy at this time.
As shown below, only the fields specified in the Outlook configuration policy show up when the contact is accessed from the native contacts app. All other fields are blanked out. Even if I add the additional data to the fields, such as a phone number, the field will show up populated in the native contacts app then disappear when the policy refreshes (the update to the field will retain in Outlook though).
If you continue to see the fields that are blocked, try waiting a few minutes and disabling and re-enabling contact sync in Outlook.
Finally, when the email profile is removed from Outlook so are the sync'd contacts from the native contacts app.
For MDM enrolled iOS devices, if contacts do not sync with the native contacts app after going through the steps above, because of certain Apple restrictions, you may need to toggle these settings to "Not configured". There is a support post on this topic that is worth reading with additional tips: https://blogs.technet.microsoft.com/intunesupport/2018/04/17/support-tip-ios-11-3-and-native-contacts-app/