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

# Set Allo as your default calling app

> Turn on System Calling in the Allo mobile app so calls you start by tapping a number in a CRM, a browser, or any other app go through Allo, on Android and iPhone

To make Allo your default calling app, go to **Settings** > **System Calling** in the Allo mobile app and select Allo in your phone's settings. Calls you start by tapping a phone number in another app then go through Allo, which is what makes click-to-call work in CRM apps such as HubSpot, Salesforce, and Odoo.

System Calling works on Android and iPhone. You set it up once per device.

## How to turn on System Calling

<Tabs>
  <Tab title="Android">
    <Steps>
      <Step title="Open System Calling in Allo">
        Open the Allo mobile app, tap **Settings** in the bottom navigation, then tap **System Calling**. Allo opens the Android **Calling accounts** screen.
      </Step>

      <Step title="Turn on the Allo calling account">
        Tap **All calling accounts** and turn on **Allo**, then go back to **Calling accounts**.
      </Step>

      <Step title="Make calls with Allo">
        Under **Make & receive calls**, tap **Make calls with** and select **Allo**. This option shows your carrier (for example, T-Mobile) until you change it.
      </Step>

      <Step title="Test it">
        Tap a phone number in your browser or your CRM app and check that the call goes through Allo.
      </Step>
    </Steps>
  </Tab>

  <Tab title="iPhone">
    <Steps>
      <Step title="Open System Calling in Allo">
        Open the Allo mobile app, tap **Settings**, then tap **System Calling**. Allo opens its page in iOS Settings.
      </Step>

      <Step title="Select Allo as the default">
        Tap **Default Calling App** (it shows **Cellular** until you change it), then select **Allo**. To come back to this screen later, go to **Settings** > **Apps** > **Allo** > **Default Calling App**.
      </Step>

      <Step title="Test it">
        Tap a phone number in Safari or your CRM app and check that the call opens in Allo.
      </Step>
    </Steps>
  </Tab>
</Tabs>

<Info>
  System Calling is set per device. If you reinstall Allo or reset your phone, turn System Calling on again.
</Info>

## What System Calling changes

With System Calling on, a call you start by tapping a phone number in another app goes through Allo instead of your mobile carrier. This applies to:

* CRM apps with click-to-call, such as HubSpot, Salesforce, Pipedrive, and Odoo
* Phone numbers in web browsers
* Phone numbers in emails, messages, and other apps

With System Calling off, those calls go through your carrier (iPhone shows this as **Cellular**) and do not use your Allo number.

## Troubleshooting

<AccordionGroup>
  <Accordion title="The call does not go through Allo when I tap a phone number">
    1. In the Allo mobile app, go to **Settings** > **System Calling**. On Android, check that **Make calls with** shows **Allo**. On iPhone, check that **Default Calling App** shows **Allo**.
    2. Check that the number includes the country code (for example, +33 or +1).
    3. Close and reopen Allo, then restart your phone.
  </Accordion>

  <Accordion title="Allo is not in the list of calling apps">
    * **Android:** in **Calling accounts** > **All calling accounts**, check that **Allo** is turned on. A calling account that is turned off does not appear under **Make calls with**.
    * **iPhone:** update iOS and the Allo app to their latest versions, then go to **Settings** > **Apps** > **Allo** > **Default Calling App** again.

    If Allo is still missing, [contact support](/en/support/contact).
  </Accordion>

  <Accordion title="Allo is no longer my default calling app">
    Go to **Settings** > **System Calling** in the Allo mobile app and select Allo again, as in the steps above.
  </Accordion>

  <Accordion title="Click-to-call does not work in my CRM app">
    1. Check that System Calling is on (see the steps above).
    2. Check that your CRM integration shows as connected in Allo under **Settings** > **Integrations**.
    3. Check that your CRM app supports click-to-call. Each integration page has a **Click-to-call** section. See [all integrations](/en/integrations/overview).
    4. Update your CRM app to its latest version.
  </Accordion>

  <Accordion title="Allo opens but the call does not start">
    1. Allow microphone and contacts access for Allo in your phone's settings. On Android, also allow the phone permission.
    2. On Android, clear the Allo app cache: **Settings** > **Apps** > **Allo** > **Storage** > **Clear cache**.
    3. Reinstall Allo. If the call still does not start, [contact support](/en/support/contact).
  </Accordion>
</AccordionGroup>

## Related pages

<CardGroup cols={2}>
  <Card title="CRM integrations" icon="https://mintcdn.com/themobilefirstcompany/RgYoir1kmfhXIZ06/media/allo-icons/Integrations.svg?fit=max&auto=format&n=RgYoir1kmfhXIZ06&q=85&s=17a406f2c623aa3c0ff4eec866c23c96" href="/en/integrations/overview" width="24" height="24" data-path="media/allo-icons/Integrations.svg">
    Connect HubSpot, Salesforce, Odoo, and other CRMs
  </Card>

  <Card title="Contact support" icon="https://mintcdn.com/themobilefirstcompany/yN5XCm7zDDPr0-yn/media/allo-icons/chat-bubble.svg?fit=max&auto=format&n=yN5XCm7zDDPr0-yn&q=85&s=d1817ba8f8b3a0d440cf67199eb899cd" href="/en/support/contact" width="24" height="24" data-path="media/allo-icons/chat-bubble.svg">
    Get help from the Allo team
  </Card>
</CardGroup>


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