> For the complete documentation index, see [llms.txt](https://docs.hackle.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.hackle.io/en/development-guide/sdk/user-identifier/crm-subscription.md).

# CRM Properties

The Hackle SDK manages properties used for CRM separately.

CRM properties are not stored on the client and are stored securely only on the server.

## Phone Number Management

{% hint style="info" %}
If you have already collected phone numbers of existing subscribers, consider [bulk import](/en/crm-marketing/crm-properties/collect-phone-number.md#import).
{% endhint %}

You can collect phone numbers for receiving text messages and KakaoTalk messages.

## Subscription Consent Management

The Hackle SDK manages separate properties to track each user's CRM Marketing message subscription consent status.

CRM Marketing messages provided by Hackle include the following:

* Push Message
* Kakao Message
* Text Message / SMS

### Message Purpose Classification

Subscription consent status can be managed differently per message purpose.

* Promotional
* Informational

{% hint style="warning" %}
Additional message classifications for special purposes beyond Promotional and Informational will be added in the future.
{% endhint %}

### Message Subscription Consent Status

<table><thead><tr><th width="215.3671875">HackleSubscriptionStatus</th><th>Description</th></tr></thead><tbody><tr><td><code>UNKNOWN</code></td><td>Has not subscribed or unsubscribed. <em><strong>(default)</strong></em></td></tr><tr><td><code>SUBSCRIPTION</code></td><td>Explicitly subscribed</td></tr><tr><td><code>UNSUBSCRIPTION</code></td><td>Explicitly unsubscribed</td></tr></tbody></table>

{% hint style="danger" %}
**When a user is newly created, the subscription consent status is UNKNOWN.**

You can send messages to users by subscription consent status in the Hackle Dashboard.

* Target users who have explicitly subscribed (SUBSCRIPTION)
* Target users who can receive messages (UNKNOWN + SUBSCRIPTION)
  {% endhint %}


---

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