You can specify a device preference (Mobile or All) for any text, dynamic search, image, or display ad, except for expanded text ads and responsive display ads.
If an ad group has both mobile-preferred and regular ads, only mobile-preferred ads serve on mobile devices, and only regular ads serve on computers and tablets.
- In the type list, select Ads and choose the type of ad you’d like to update.
- Select one or more ads.
- Under "Device preference" on the edit panel, select Mobile or All.