> For the complete documentation index, see [llms.txt](https://help.sipgate.de/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.sipgate.de/cloud-telefonanlage/en/using-sipgate/mobilfunk/was-ist-der-mobile-zusatzanschluss.md).

# What is the mobile additional line?

The mobile additional line in sipgate: equip individuals or devices with mobile service easily.

There are situations in which it is enough to equip individual people or even devices with mobile service, without you having to book or create them for these new users in the phone system. This is possible with the feature **mobile additional line** possible.

This means you can, for example, provide employees who want to be reachable on the go and can also make calls and use mobile data. Alternatively, devices such as surveillance cameras, alarm systems and card readers can be conveniently equipped with mobile service via the mobile additional line. And several employees then have independent access to them.

With the mobile additional line, unlike with newly created users, **not** the full range of the sipgate phone system can be used. For example, **no voicemail or event list** available.

## Where can I find the feature?

The starting point for user-independent mobile service is the [**mobile service tile**](https://app.sipgate.com/mobile-telephony) in the **account management**. Here, click on **book mobile options**.

![sipgate-Hilfecenter-Mobilfunk3.png](https://4045603198-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fg0qj71PeONPljdPedXLf%2Fuploads%2Fgit-blob-a37e3cbfce57eb08afe86c32d6bb153ea8858d69%2Fsipgate-Hilfecenter-Mobilfunk3.png?alt=media)\
Then select in the next step **mobile additional line**.

After you have assigned the **device name** you then add a phone number.

{% hint style="warning" %}
**Important:** Please note that for this feature **only mobile numbers** can be used. Landline numbers are not available for this feature.
{% endhint %}

If your **Sender number** is to be the same as the phone number added previously, you must enter it manually in the **device settings** the corresponding **device card** manually.

![sipgate-Hilfecenter-Mobilfunk5.png](https://4045603198-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2Fg0qj71PeONPljdPedXLf%2Fuploads%2Fgit-blob-1a119d1c04309b1e5f4661fcc8e303c7bbf95aca%2Fsipgate-Hilfecenter-Mobilfunk5.png?alt=media)


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