devicetype 2 means Personal Computer
Desktop and laptop computers, usually browser traffic that arrives with a site object.
When to send it
Send 2 when the ad will render on a desktop or laptop computer. It is the normal value for desktop web requests, which carry a site object, and for desktop applications that request ads directly. It has been in the list since OpenRTB 2.0.
Buyers map 2 to desktop creative sizes and desktop pricing, and many CTV and mobile campaigns exclude it outright. The costly error runs the other way: smart TV browsers, game consoles, and some streaming players send user agent strings that look like desktop browsers, so a seller that derives Device.devicetype from the user agent alone can label television inventory as 2. A TV should be 3 or 7, and other connected boxes 6. Tablets in desktop browsing mode cause the same problem in a smaller way.
Example
{
"device": {
"devicetype": 2
}
}Fields that carry it
Other values in device types
The device types list page explains the whole list and its common mistakes.