I have a Flutter white labeled project, i want to use only the Firebase Auth on login module of all differents apps i'll generate, can i make it with only one Firebase Project and work with the UID response on the backend after the login completes? What's the best practice?
firebaser here
The recommended practice is to use a project only for single family of apps, with a single set of users. So an example of this would be to have the iOS, Android, and web versions of your app, and maybe an administrative back-end you have for that same app, and then maybe pro versions for all platforms too.
White labeling the same app for many customers should be done with a separate project for each of those customers. Otherwise you'll quickly run into limitations, such as the number of API keys you can create in a single project.