app-ads.txt

App-ads.txt works exactly like ads.txt but for mobile app inventory. It's a text file hosted on the developer's website (the domain listed in the app store) that declares which ad networks and exchanges are authorized to sell ad space within the app.

If you have a mobile app that shows ads, you need app-ads.txt. Without it, advertisers can't verify your inventory's legitimacy, and you'll miss out on premium demand. The format is identical to ads.txt — list each authorized seller with their domain, account ID, relationship type, and optional TAG ID.