[jkwchui]

Hi, the tutorial writer here. The first few paragraphs in the tut would give you a sense of what Ash does, but thank you for the comment that its role in comparison with Phoenix should be spelt out at some point. Ash helps provide a thoughtful underpinning to structure your data, and Phoenix / LiveView presents it to the world. If you are a poetry person:

Phoenix rise from Ash.