Ionic Platform Auth & own Backend

We have our Java rest custom backend for a ionic app.
At the moment the app Authenticate with the backend with Baerer token.
We are evaluating to use Ionic Platform with all services offered, but one question arise.
Once logged to Ionic Platform ho to pass user logged to our backend?
I didn’t find any reference



I want to know this too.

Is there any way possible to do that, or Ionic Auth is not support this way?