The app-ads.txt file is a text file which provides a mechanism for publishers to declare their authorized digital sellers. Created by IAB, it is an extension of the original ads.txt standard that was used for the same purpose in web advertising. It helps ad networks and DSPs easily verify whether an ad network or exchange they are buying your traffic from is actually allowed to sell it.
Adding app-ads.txt augments trust between advertisers, demand partners and publishers. If publishers do not have their own website where they can place an add app-ads.txt file, premium brand demand may be unavailable to them.
If you don't have app-ads.txt file yet:
Add developer website URL to your Google Play and App Store apps.
Download Appodeal's app-ads.txt from this page.
Upload app-ads.txt file to the root path of your developer website (it should look like this: example.com/app-ads.txt).
If you already have app-ads.txt:
Copy Appodeal's app-ads.txt from this page.
Paste the content to your app-ads.txt.