How to add a CalDAV account to your iPhone or iPad

Email > Webmail/SmarterMail
  1. Launch the Settings app on your iPhone or iPad.
  2. Tap on Mail, Contacts, Calendars.
  3. Tap on Add Account... under the Mail section.
  4. Tap on Other.
  5. Tap on Add CalDAV Account under the Other section.
  6. Enter all the information necessary for your CalDAV account. If you don't know this information, you'll need to get it from a system administrator or from whoever set up your CalDAV account.
  7. Tap the Next button in the upper right hand corner and your iPhone or iPad will verify the account.
  8. If everything looks right, just tap on Done and that's it. Your CalDAV account will now start syncing with your iPhone or iPad.