The purpose of the Traffic objective is to drive people to a destination such as your website or your mobile app.
When you set up a campaign with a Traffic objective, you will need to consider:
Whether you want to drive traffic to a website or app
If you choose App, whether you will target people who already have your app.
Note: You can target people (Custom Audience) who previously installed your app by selecting this in the Audience section of your ad group creation. Learn more about custom audiences.
Watch the video below for more information on the Traffic advertising objective.