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.

t-online.de app-ads.txt check

t-online.de 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. 396 lines, 370 unique records, 0 duplicates, 0 invalid lines, 12 ad networks detected.

Ad networks in t-online.de/app-ads.txt

Magnite (Rubicon) — account 16728: 1 line in the file
Amazon Publisher Services — account 3505: 1 line in the file
Xandr (Microsoft) — account 15027: 1 line in the file
Google AdMob — accounts pub-8430527671881951, tonline: 2 lines in the file
Mintegral — partner (reseller) lines only: 10 lines in the file, 400 expected lines missing
BIGO Ads — partner (reseller) lines only: 12 lines in the file, 400 expected lines missing
Yango Ads — partner (reseller) lines only: 29 lines in the file, 400 expected lines missing
DSP Exchange — partner (reseller) lines only: 18 lines in the file, 400 expected lines missing
Maticoo (zMaticoo) — partner (reseller) lines only: 16 lines in the file, 400 expected lines missing
Verve (PubNative) — partner (reseller) lines only: 24 lines in the file, 400 expected lines missing
Start.io — partner (reseller) lines only: 10 lines in the file, 147 expected lines missing
Bidmachine — partner (reseller) lines only: 39 lines in the file, 400 expected lines missing

Corrected file: t-online.de app-ads.txt (fixed).

FAQ

Does t-online.de have an app-ads.txt?

Yes — https://t-online.de/app-ads.txt has 396 lines (checked 20 Oct 2026).

Which ad networks does t-online.de work with?

Its app-ads.txt lists Magnite (Rubicon), Amazon Publisher Services, Xandr (Microsoft), Google AdMob, Mintegral, BIGO Ads, Yango Ads, DSP Exchange, Maticoo (zMaticoo), Verve (PubNative), Start.io, Bidmachine.

Is the app-ads.txt of t-online.de correct?