Getting started with XMPP
XMPP is a network protocol or specifically Its a texting "app" for people you care about. In Its nature, XMPP has a lot of features that you wouldn't get from other messaging "app" because It can be extended with extensions. The extensions I mean are not an app but rather a bunch of protocols specification that utilised XMPP.
You can host It yourself and connect with other people without worryin' about three-letter agencies listening to your circlejerk broskies. And because Its decentralise nature, there's a bunch of clients for It. XMPP has a page list of clients, go check it out to know more.
Clients
For androidfag I personally recommend Conversations over Monocles, because It remains as a chat "app" instead tryin' to be whatsapp clones. And for desktop users I would recommend gajim. Check XMPP client list page for the devices I didn't mentioned.
Using it
Most of the clients are created to be easy to use. If you find them hard to use just don't use it and use another client till you found something suit you or create one for yourself. When you decided to use XMPP, I assure you, you'll gain something and lose something. Convincing normalfags to use it too also a chore, and atleast for me It act as a filter.