Set up CardDAV on your iPhone or iPad When you add your CardDAV account, you can sync your Contacts with your iOS device. Add your CardDAV account Tap Settings > Contacts > Add Account > Other .  If you're adding another account, tap Accounts > Add Account. Tap Add CardDAV Account. Enter CardDAV information Enter information as below, then tap Next. You can also enter an account description. Server my.mailhappen.com User Name your email address Password your password Done The CardDAV account is added. You can use Contacts App to see all your contacts.