I’d consider Phoenix to be like Flask. Ash fills the gap that brings Phoenix up to feature parity with a batteries included framework like Django.

Ash Admin (Django admin), Ash Resource & Domain (Django models & ORM), Ash JSON (Django Rest Framework), Ash Auth (Django Allauth), Ash Phoenix (Django Forms), Ash policies (Django permissions)

But you aren’t required to use Phoenix with an Ash project. Ash will happily work as a standalone CLI, terminal app or some other Elixir web framework that comes out tomorrow.