app-ads.txt implementation for App Publishers


Understanding app-ads.txt

In 2018, the IAB launched ads.txt, a file enabling web publishers to designate authorized digital sellers of their ad inventory. app-ads.txt is the mobile in-app equivalent of this specification, which mobile app publishers can implement. This text file declares your Authorized Digital Seller (ADS) List to prevent unauthorized sellers from gaining off your inventory or from selling spoofed inventory.

App Publishers can use the app-ads.txt file to indicate authorized digital sellers of their ad inventory and DSPs can use it to validate that they are buying inventory through an authorized source. Although the implementation is optional, its strongly recommended to implement it for the purpose of transparency.

Implementing app-ads.txt

To implement app-ads.txt:

  1. Provide a developer website in your app store listings. Ensure that the proper developer website URL is accessible in the developer website section of the app store.
  2. Publish an app-ads.txt file. Create this document in Notepad, and include the following data:
    • Ad Source Domain: This value is the domain URL of the authorized seller of your app inventory. For e.g.,
    • Publisher ID: This the unique id assigned to you by your authorized seller
    • Type of Relationship: Publisher relationships could be direct or in certain cases indirect. If you own the app inventory then you can choose “Direct”
    • Ad Source ID: This is the ad source’s TAG ID which is unique to your authorized seller.

Here is an example of an entry in an app publisher’s app-ads.txt file. The four parameters are separated by commas, with a separate line for each authorized partner:, [pub id], DIRECT, [source id]

Publish the app-ads.txt file in the root folder of the app developer’s developer website; for example,

Although implementation is optional, its strongly recommended for all publishers and DSPs to adopt app-ads.txt as a best practice to help further ad tech industry’s overall transparency and trust.

Please refer to the IAB Tech Lab’s specification for more details.

For more information on GeoSpot Media’s global reach of publishers who are app-ads.txt compliant, feel free to reach out to