> For the complete documentation index, see [llms.txt](https://docs.transparentedge.eu/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.transparentedge.eu/getting-started/faq/cabeceras-por-defecto/x-device.md).

# X-Device

Transparent Edge can use the User-Agent header to determine the type of device that is connecting and categorize it as a desktop, mobile, or tablet.

To identify the device, Transparent Edge includes a header called X-Device in both the request to the origin and the response to the client. This header can have three values:

* desktop
* mobile
* tablet

Depending on the value of this header, Transparent Edge saves a version of each object for that device, making it possible to serve different content for each type of device under the same URL.[![Edit](https://soporte.transparentcdn.com/images/edit.png)](https://soporte.transparentcdn.com/projects/incidencias/wiki/Detecci%C3%B3n_de_dispositivos_m%C3%B3viles/edit?section=2)

### Force device (feature available on request)

Even if the device is detected, it's possible to, for instance, force a mobile device to display a desktop version. We do this using the Force-Device cookie. If this cookie is present, it takes priority over X-Device.


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