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Until recently my wife and I shared one Apple ID to allow us to have synced calendars and contacts. The only thing she used her ID for was the Messages app. When I learned that I could set her phone up with both of our IDs and then choose which one it pulls from for each item I changed to this approach. So now the only things turned on for my ID on her phone are Calendars and Contacts.
This works great other than on her phone under the "Contacts" heading of "Mail, Contacts, Calendars" it has my info selected. If she changes it on her phone it will update mine as well.
Does anyone have a better solution for how we can sync our contacts book (other than using a 3rd-party service like Google)? Thanks.