How do I disable Contact Syncing?

iPhone:

1. Go to the iPhone Home screen 
2. Go to 'Settings' > 'General' > 'Profiles'
3. Tap 'Haystack'
4. Tap 'Delete Profile'

This will be remove all Haystack cards from your phone contacts.

Android:

1. Tap on the 'three lines' at the top > Settings
2. Toggle 'Contact Syncing' to be off