Limitations of enhancing my mobile app with Jitsi calls

Developers Jitsi Meet API
1

I am building a mobile chat app and I am wondering how I can use Jitsi SDKs to add audio calls and the limitations of it. So 3 questions:

  1. Should I include the Jitsi logo or a message in the app? Maybe embedding the entire call in a separate view of my app (that includes Jitsi UI).
  2. Can I use https://meet.jit.si infrastructure without limitations?
  3. There are other mobile apps or web apps doing it?

Thanks in advance!