> For the complete documentation index, see [llms.txt](https://developer.mediarithmics.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.mediarithmics.io/user-points/user-identifiers/networks-ids/device-based-network-ids/custom-device-id-integration.md).

# Custom Device ID integration

A **UserPoint** can be associated with multiple **UserDevicePoint**. Each user device point can include:

* Multiple device technical identifiers
* One device information record

### Create a new registry

1. Go to **Navigator > Settings > Organisation > Device Registries.**
2. In the **First-party device registries** section, click on **New Registry.**
3. Specify the following details:

<table data-full-width="false"><thead><tr><th width="219">Parameters</th><th>Description</th></tr></thead><tbody><tr><td>Name</td><td>Name of the Device Registry</td></tr><tr><td>Token</td><td>A technical identifier used to link the Device Registry with the JS Tag</td></tr><tr><td>Type</td><td><p>Must be one of the following enums: </p><p><code>MOBILE_VENDOR_ID</code> ,<code>CUSTOM_DEVICE_ID</code></p></td></tr><tr><td>Description</td><td>(Optional) More information about the Device Registry</td></tr></tbody></table>

### Subscribe to an existing registry

1. Go to **Navigator > Settings > Organisation > Device Registries.**
2. In the **Shared device registries** section, click on **Manage subscriptions.**
3. Select **Subscribe** to the desired registry.

If you have multiple datamarts, don't forget to activate your **Device Registry** on all datamarts.


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