Inform your user to download the Iris ID app in the App Store or Google Play.
Using the token received in the previous step, generate a link or a button with the following href (the format is the same for iOS and Android): iris:///?token=TOKEN
Display the link or button to the user, or automatically redirect to the href. Clicking on the link or button, or being automatically redirected, will open the Iris ID app and start the session.
Once the user has completed the session, you will receive a callback to the URL provided in the previous step.
The Iris ID app can also automatically redirect the user at the end of the flow.
To enable this behavior, append a redirect URL to the href: iris:///?token=TOKEN&redirect_url=REDIRECT_URL
Where REDIRECT_URL is a valid URL in URI encoded format. This URL can be e.g. a web address but it could also be a deeplink to another app.