title: How to handle Firebase Registration IDs(tokens) when multiple users use the same device to access the same app
body: <p>Is a firebase token ID based on the device's characteristics, such as IMEI for phones, MAC for PC, etc.. ?</p>
  
  <p>My primary concern is the following:</p>
  
  <p>Multiple users use a given device to access the same app ( Think FB ).</p>
  
  <ol>
  <li>User 1 logs to the app and Firebase provides a token ( E.g. FirebaseInstanceId.getInstance().getInstanceId() ).</li>
  <li>User 1 does a logout</li>
  <li>User 2 logs in.</li>
  <li>Is the same Firebase registration token from #1 going to be used now for User 2?</li>
  </ol>
  
  <p>Is a new firebase ID generated for User 2 or is this something that needs to be handled manually by the app itself?
  I have the feeling that this is more a responsibility of the app developer where they monitor who logs in and so forth and the old registration ID is cancelled while a new one is generated for this new login ?</p>
  
  <p>Just to clarify - I only use Firebase Cloud Messaging and nothing else from Firebase so I will be managing the notifications from my own server. This means that I will be storing the Firebase registration IDs in my own database to know for which Firebase Registration ID to generate a notification (e.g. user receives a message from another user), for example.</p>