app-ads.txt
The version of ads.txt for mobile and connected-TV apps. It lists the companies authorized to sell an app’s advertising inventory.
What is app-ads.txt?
app-ads.txt is the IAB Tech Lab extension of ads.txt for mobile, tablet and connected-TV applications. Because apps do not have a web root of their own, the file is hosted on the developer website that appears in the app store listing, and buyers link the two through the store URL carried in bid requests. The format is the same as ads.txt: one line per authorized ad system, account ID and relationship type. It helps buyers detect bundle-ID spoofing, where unauthorized sellers misrepresent which app an impression comes from.
How app-ads.txt works
The app developer publishes the file on the website named in the app’s store listing. Buyers match the app to that site and check the file.
- The developer confirms the website listed in each app’s store page.
- It creates a plain-text app-ads.txt file listing every authorized SDK, mediation partner and exchange account.
- The file is uploaded to the root of that developer domain.
- Buyers look up the app in the store, find the developer domain and crawl the file.
- Bid requests are checked against the file, and unlisted sellers are flagged or declined.
Why it matters
It extends the same protection against unauthorized selling to app inventory.
For publishers
App developers that keep the file current avoid losing bids from buyers that only purchase authorized app inventory.
For advertisers
It provides assurance that app impressions are sold by parties the developer has actually approved.
Practical example
A game developer adds a new demand partner and updates app-ads.txt so that buyers treat the partner as authorized.
Key considerations
- A single file on the developer domain covers all apps that list that domain, so entries must reflect every app’s partners.
- Mismatches between the store listing URL and the hosting location are a frequent reason files are not found.
- Mediation partners usually supply the exact lines to add; copying them precisely avoids parsing errors.
More Mobile Advertising terms
Frequently asked questions
Where is app-ads.txt hosted?
On the root of the developer website listed in the app’s store page, not inside the app itself.
Does app-ads.txt apply to CTV apps?
Yes. Connected-TV apps use the same standard, with the developer domain taken from the relevant TV app store listing.
How often should it be updated?
Whenever a demand or mediation partner is added or removed, and as part of a regular review of active partners.