Haystack automatically synchronizes Haystack card data to your phone contacts.
Whenever changes are made to a Haystack card, the new details are automatically updated in your phone contacts.
If you do not want your Haystack cards to sync to your phone's contacts, you can untick this option in settings. Doing this will be remove all Haystack card details from your phone contacts.
Note: The app does not sync your phone's contact into Haystack.