> ## Documentation Index
> Fetch the complete documentation index at: https://docs.stackone.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Customer.io Changelog

> Release history for the Customer.io connector. Each version lists what changed and which actions were affected.

<Card title="Customer.io connector" icon="arrow-left" href="/connectors/customerio" horizontal>
  Back to the connector overview, authentication methods, and actions.
</Card>

<Update label="v2.1.0" description="16 Sept 2026">
  `data-sync` `new-feature`

  Enabled Data Sync on 9 App API list actions, so activities, exports, messages, newsletters, reporting webhooks, segments, sender identities, snippets and transactional messages stay in sync.

  <AccordionGroup>
    <Accordion title="Changed · 9 actions updated">
      `customerio_list_activities`, `customerio_list_exports`, `customerio_list_messages`, `customerio_list_newsletters`, `customerio_list_reporting_webhooks`, `customerio_list_segments`, `customerio_list_sender_identities`, `customerio_list_snippets`, `customerio_list_transactional`
    </Accordion>
  </AccordionGroup>
</Update>

<Update label="v2.0.0" description="28 Jul 2026">
  `auth-improvements`

  Split the single API Key auth into two separate auth methods - App API Key (bearer) and Track API Key (basic) - so each shows only its own required fields and test action.
</Update>