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.

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

Checked 20 Oct 2026. 58 lines, 58 unique records, 0 duplicates, 0 invalid lines, 4 ad networks detected.

Google AdMob — accounts pub-1883474157636614, pub-1308422813430251, pub-9445724340928127: 3 lines in the file
Meta Audience Network — account 329663631464502: 1 line in the file
ironSource / LevelPlay — partner (reseller) lines only: 13 lines in the file, 112 expected lines missing
Yango Ads — partner (reseller) lines only: 19 lines in the file, 400 expected lines missing

Yes — https://farpoem.com/app-ads.txt has 58 lines (checked 20 Oct 2026).

Its app-ads.txt lists Google AdMob, Meta Audience Network, ironSource / LevelPlay, Yango Ads.

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