The Instance ID API lets you integrate Instance ID with your Android
or iOS app. Instance ID provides a unique identifier for each instance of
your app and a mechanism to authenticate and authorize actions, like sending
messages via Google Cloud Messaging. The
InstanceID is long
lived, but may expire for the following reasons:
- Device factory reset.
- User uninstalls the app.
- User performs “Clear Data” in the app.
- Device unused for an extended period (device and region determines the timespan).
- Instance ID service detects abuse or errors and resets the
- Server-side code if your client app requires that functionality.
The Instance ID service notifies your app of an
InstanceID reset via
callback to a
InstanceIDListenerService. If your app receives this
notification, it must call
getToken() and retrieve the new
and update its servers.
getToken method to prove the ownership of the
InstanceID and to allow
servers to access data or services associated with the app. The method follows
the patterns of OAuth2, and requires an
authorizedEntity can be a project ID or another
InstanceID, and it determines
the services that are authorized to use the generated token. The
determines the specific service or data to which the token allows access.
Learn more about the Instance ID API for: