Yes it has been done and to a greater extent than your dismissive comment. It still doesn't detract from the noteworthiness of the OP.

I don't think it was dismissive at all. When a post rises to the front page of HN people are going to post comments both agreeing or disagreeing. In my case, I don't see what all the hoopla was about or how this was upvoted to page 1

The biggest difference in this case is that the mobile version is native instead of using a WebView.

Yes, it uses JS in the background but uses native widgets, which results in a much better user experience.

It has, but look... It's a good example code base and has lots of notes on what technologies are used incase you are interested in doing the same thing...