The author of the post is really using an iPad Pro and a remote Linux server together for software development. With that combination, all the above that you mention is of course easy to do from an iPad.
- with an Apple Pencil, it’s a very useful device for sketching out ideas (much like a piece of paper is, but with some neat advantages, e.g., infinite size, scalability, editing),
- with the keyboard and any text editor, it’s useful for banging out text, e.g. a rough draft of a blog post or paper...
Of course, it will likely take a while before developers are able to publish apps that utilize these new permissions to the Store.