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.

notadevstudio.github.io achieves the best ad optimization: its app-ads.txt has no errors and matches what its 4 ad networks expect (100% of 4 lines).

Checked 20 Oct 2026. 124 lines, 123 unique records, 1 duplicates, 0 invalid lines, 6 ad networks detected.

Google AdMob — account pub-9540801395541814: 1 line in the file
Meta Audience Network — account 2490461594741277: 1 line in the file
TripleLift — account 7677: 1 line in the file
Xandr (Microsoft) — account 280: 1 line in the file
Mintegral — partner (reseller) lines only: 18 lines in the file, 400 expected lines missing
Yango Ads — partner (reseller) lines only: 18 lines in the file, 400 expected lines missing

Yes — https://notadevstudio.github.io/app-ads.txt has 124 lines (checked 20 Oct 2026).

Its app-ads.txt lists Google AdMob, Meta Audience Network, TripleLift, Xandr (Microsoft), Mintegral, Yango Ads.

notadevstudio.github.io achieves the best ad optimization: its app-ads.txt has no errors and matches what its 4 ad networks expect (100% of 4 lines).