Why app-ads.txt needs a website
app-ads.txt lists the ad networks allowed to sell your app's ad space. Ad buyers only trust it when it sits at the root of the website in your store listing, so they read the "developer website" from Google Play or the App Store and fetch /app-ads.txt from there. Without that file, buyers can't verify your app: many skip it, and AdMob warns that you may lose revenue. If you don't have a website, an AppPage site is one in a minute.
Where to set the website
Google Play
In Play Console, open your app and go to Store settings (under Grow users › Store presence). In Store listing contact details, set Website to https://yourapp.apppage.net and save. The change shows on your store page without a new release.
App Store
In App Store Connect, open your app, choose the version and set the Marketing URL to https://yourapp.apppage.net; ad networks read it from the "Developer Website" link on your App Store page. Set the Support URL to the same site too: your AppPage site has a support page. Marketing and Support URLs can be changed without a new build.
Which lines go in the file
- AdMob: AdMob shows your line under Apps › View all apps › app-ads.txt. It looks like
google.com, pub-…, DIRECT, f08c47fec0942fa0with your own publisher ID. - Mediation networks (AppLovin, Unity, ironSource, Meta, Mintegral, Pangle…): each network gives its own lines in its dashboard or docs. Add them all.
- One file for all your apps: app-ads.txt belongs to the website, so every app that lists the same website shares it. Put the lines for all your accounts in one file.
Not sure which networks your app uses? The SDK detector finds the ad SDKs in your app and compares them with your app-ads.txt.
"app-ads.txt not found" and other problems
- The store listing points somewhere else. The website in the listing must be the site with the file, on the same domain.
- The change hasn't reached the store page yet, or the ad network hasn't crawled again. AdMob can take a day or more; use Check for updates.
- A wrong publisher ID or a typo. One wrong character makes the line useless. The checker validates each line and your AdMob publisher ID.
- The app was just published. Ad networks may not have the store listing yet.
Your own domain
If your AppPage site uses your own domain, the file is served at yourdomain.com/app-ads.txt; use that domain as the developer website. Changing the developer website later means waiting for the ad networks to crawl again, so pick one and keep it.
What else comes with the site
The same free site gives your app the pages the stores ask for: a privacy policy, terms, an account deletion page and a support page, all at their own addresses on yourapp.apppage.net.