Is there a typical messenger architecture?

Question

Android

I want to write my own messenger, of course, with my own features, since there are already many of them. Is there any typical architecture for such applications?
What modules should be and how they interact.
PS I am writing for personal experience, without the mania of fame / wealth or anything else.

Answer 1

Many years have passed, I have upgraded my skills and I know that there is no answer to this question. Thanks to all)

Answer 2

XMPP is an open protocol and well defined. In addition, there are a bunch of XEPs that are about "features"

Answer 3

Check out Xabber , Open Source, 500k+ downloads on Google Play.