A Flutter plugin to retrieve the Firebase App Instance ID# device_unlock
How does it work
App Instance Id is an unique identifier for an instance of the app. In other words, each user/installation has such a value. It is a 32-character hex number like a12bc3d456789efabc123456a8a5de56.
OBS.: The project should have firebase configured for this plugin to work.
var instanceId = await FirebaseInstanceId.appInstanceId ?? 'Unknown installation id';