^^following up, would this generally mean that a shared view model could cover this need for each fragment to be backed by a viewmodel (instead of each fragment having a standalone VM)? I don’t see why not, but a little more research has shown that a shared view model can be an efficient way to handle passing data between fragments.

I think that the SharedViewModel does not replaces the specific ViewModel. The specific one has use cases/access/data to that screen and the shared one has the data that needs to be shared. They can work together if needed.

so it would be more sound architecturally to have a shared VM that takes care of shared data, and a unique VM for each fragment, versus just a shared VM that handles both the shared and unique data for each screen. On the one hand, less view models, on the other hand, more specific view models…

The problem having only one is the possibility to call a function on Fragment A that is only related to Fragment B. This can be a problem of scoping and messy when the project grows.

Gotcha. Thanks Igor 😃

Another alternative to data communication is an EventBus of some kind.