80.4 Associating the App with a Website

By default, Android will provide the user with a range of options for handling an app link using the panel shown in Figure 80-1. This will usually consist of the Chrome browser and the target app.

Figure 80-1

To prevent this from happening the app link URL needs to be associated with the website on which the app link is based. This is achieved by creating a Digital Assets Link file named assetlinks.json and installing it within the website’s .well-known folder. Note that digital asset linking is only possible for websites that are https based.

A digital asset link file comprises a relation statement granting permission for a target app to be launched using the web site’s link URLs and a target statement declaring the companion app package name and SHA-256 certificate fingerprint for that project. A typical asset link file might, for example, read as follows:

[{

    "relation": [...