A marketer at an agency works on app campaigns for a food delivery company. They are running a campaign to get new users. Which one of the following is the optimal bidding strategy for the client to meet their objective?

tCPI (target Cost Per Install) is the optimal bidding strategy for acquiring new app users because it directly optimizes for installations at a target cost you define. This aligns perfectly with the objective of getting new users. CPM (Cost Per Mille/thousand impressions) focuses on impressions, not user acquisition, and doesn't guarantee installs. CPC (Cost Per Click) optimizes for clicks, which are a step before an install and don't guarantee user acquisition. tROAS (target Return On Ad Spend) is used for optimizing for in-app actions with revenue, which is more suitable for re-engagement or maximizing lifetime value from existing users, not initial user acquisition.