I like this article for many reasons:

1. I started Flutter in a simple way, just wrapping a web app generated by Google Earth Engine and this article seems a good way to go further;
2. It’s very long and shows the limits of the format used by Medium. There is no way to collapse the chapters to make the article easier to grasp.
3. It shows the interest of the good-old way to read a document: take notes separately on paper to unload your mind, instead of reading it the urban “chat” way: try and keep in mind the whole structure of the message.

This article is worth some efforts, though.