# Extension contacts

- [Favorite](https://support.portsip.com/development-portsip/rest-apis/version-22.0/api-reference/user/extension-contacts/favorite.md)
- [Unfavorite](https://support.portsip.com/development-portsip/rest-apis/version-22.0/api-reference/user/extension-contacts/unfavorite.md)
- [Sync tokens](https://support.portsip.com/development-portsip/rest-apis/version-22.0/api-reference/user/extension-contacts/sync-tokens.md)
- [Diff](https://support.portsip.com/development-portsip/rest-apis/version-22.0/api-reference/user/extension-contacts/sync-tokens/diff.md)