Bid modifiers allow you to adjust bids for a specific criterion without changing the targeting of your campaign or ad group. For example, an ad group bid modifier for mobile devices will not exclude impressions for other types of devices, but it will allow you to raise or lower your bids for mobile impressions.
For more information on how bidding works and how to set bid modifiers, see our Bidding Guide.
Campaign bid modifiers
You can specify bid modifiers at the campaign level for the following criteria type using the CampaignBidModifierService.
InteractionTypeInfocriteria using one of the predefined InteractionType enums. Currently,
CALLis the only supported enum value for campaign bid modifiers.
Ad group bid modifiers
You can specify bid modifiers at the ad group level for the following criteria type using the AdGroupBidModifierService.