If you look at SimpleX, they have features that are unique and unfamiliar. But they don't leave users without knowledge of function and usage. There is usually there, a short description and a link for further learning. Sometimes the descriptions are just below setting buttons.

How-tos and explanations can be provided without force by giving users the choice to use the app without being bothered by pop-up tutorials. As long as the user can turn these off or click the 'x' button at the top-right....