An IAB Tech Lab standard that lets app publishers declare which ad networks are authorized to sell their inventory.

Where do I put the app-ads.txt file?

At the root of the developer website listed in your App Store / Google Play page, e.g. https://studio.com/app-ads.txt.

What is a Certification Authority ID?

An optional TAG-ID of the ad system, the 4th field of an app-ads.txt record.

kinzoo.com achieves the best ad optimization: its app-ads.txt has no errors and matches what its 2 ad networks expect (100% of 24 lines).

Checked 20 Oct 2026. 50 lines, 45 unique records, 0 duplicates, 0 invalid lines, 7 ad networks detected.

Kidoz — account 15668: 23 lines in the file
Google AdMob — account pub-1649132170553094: 1 line in the file
Unity Ads — partner (reseller) lines only: 10 lines in the file, 150 expected lines missing
Yango Ads — partner (reseller) lines only: 17 lines in the file, 400 expected lines missing
Prado — partner (reseller) lines only: 21 lines in the file, 6 expected lines missing
Verve (PubNative) — partner (reseller) lines only: 14 lines in the file, 400 expected lines missing
Bidmachine — partner (reseller) lines only: 13 lines in the file, 400 expected lines missing

Yes — https://kinzoo.com/app-ads.txt has 50 lines (checked 20 Oct 2026).

Its app-ads.txt lists Kidoz, Google AdMob, Unity Ads, Yango Ads, Prado, Verve (PubNative), Bidmachine.

kinzoo.com achieves the best ad optimization: its app-ads.txt has no errors and matches what its 2 ad networks expect (100% of 24 lines).